[Unicode]  Technical Reports
 

Unicode Technical Standard #35

Unicode Locale Data Markup Language (LDML)
Part 3: Numbers

Version 26
Editors John Emmons (emmo@us.ibm.com) and other CLDR committee members

For the full header, summary, and status, see Part 1: Core

Summary

This document describes parts of an XML format (vocabulary) for the exchange of structured locale data. This format is used in the Unicode Common Locale Data Repository.

This is a partial document, describing only those parts of the LDML that are relevant for number and currency formatting. For the other parts of the LDML see the main LDML document and the links above.

Status

This document has been reviewed by Unicode members and other interested parties, and has been approved for publication by the Unicode Consortium. This is a stable document and may be used as reference material or cited as a normative reference by other specifications.

A Unicode Technical Standard (UTS) is an independent specification. Conformance to the Unicode Standard does not imply conformance to any UTS.

Please submit corrigenda and other comments with the CLDR bug reporting form [Bugs]. Related information that is useful in understanding this document is found in the References. For the latest version of the Unicode Standard see [Unicode]. For a list of current Unicode Technical Reports see [Reports]. For more information about versions of the Unicode Standard, see [Versions].

Parts

The LDML specification is divided into the following parts:

Contents of Part 3, Numbers

1 Numbering Systems

<!ELEMENT numberingSystems ( numberingSystem* ) >
<!ELEMENT numberingSystem EMPTY >
<!ATTLIST numberingSystem id NMTOKEN #REQUIRED >
<!ATTLIST numberingSystem type ( numeric | algorithmic ) #REQUIRED >
<!ATTLIST numberingSystem radix NMTOKEN #IMPLIED >
<!ATTLIST numberingSystem digits CDATA #IMPLIED >
<!ATTLIST numberingSystem rules CDATA #IMPLIED >

Numbering systems information is used to define different representations for numeric values to an end user. Numbering systems are defined in CLDR as one of two different types: algorithmic and numeric. Numeric systems are simply a decimal based system that uses a predefined set of digits to represent numbers. Examples are Western ( ASCII digits ), Thai digits, Devanagari digits. Algorithmic systems are more complex in nature, since the proper formatting and presentation of a numeric quantity is based on some algorithm or set of rules. Examples are Chinese numerals, Hebrew numerals, or Roman numerals. In CLDR, the rules for presentation of numbers in an algorithmic system are defined using the RBNF syntax described in Section 6: Rule-Based Number Formatting.

Attributes for the <numberingSystem> element are as follows:

id - Specifies the name of the numbering system that can be used to designate its use in formatting.

type - Specifies whether the numbering system is algorithmic or numeric.

digits - For numeric systems, specifies the digits used to represent numbers, in order, starting from zero.

rules - Specifies the RBNF ruleset to be used for formatting numbers from this numbering system. The rules specifier can contain simply a ruleset name, in which case the ruleset is assumed to be found in the rule set grouping "NumberingSystemRules". Alternatively, the specifier can denote a specific locale, ruleset grouping, and ruleset name, separated by slashes.

Examples:

<numberingSystem id="latn" type="numeric" digits="0123456789"/>
<!-- ASCII digits - A numeric system -->
<numberingSystem id="thai" type="numeric" digits="๐๑๒๓๔๕๖๗๘๙"/>
<!-- A numeric system using Thai digits -->
<numberingSystem id="geor" type="algorithmic" rules="georgian"/>
<!-- An algorithmic system - Georgian numerals , rules found in NumberingSystemRules -->
<numberingSystem id="hant" type="algorithmic" rules="zh_Hant/SpelloutRules/spellout-cardinal"/>
<!-- An algorithmic system. Traditional Chinese Numerals --> 
For general information about the numbering system data, including the BCP47 identifiers, see the main document Section Q.1.1 Numbering System Data. ) >

2 Number Elements

<!ELEMENT numbers (alias | (defaultNumberingSystem*, otherNumberingSystems*, minimumGroupingDigits*, symbols*, decimalFormats*, scientificFormats*, percentFormats*, currencyFormats*, currencies?, miscPatterns*, special*)) >

The numbers element supplies information for formatting and parsing numbers and currencies. It has the following sub-elements: <defaultNumberingSystem>, <otherNumberingSystems>, <symbols>, <decimalFormats>, <scientificFormats>, <percentFormats>, <currencyFormats>, and <currencies>. The currency IDs are from [ISO4217] (plus some additional common-use codes). For more information, including the pattern structure, see Section 3: Number Format Patterns.

2.1 Default Numbering System

<!ELEMENT defaultNumberingSystem ( #PCDATA )

This element indicates which numbering system should be used for presentation of numeric quantities in the given locale.

2.2 Other Numbering Systems

<!ELEMENT otherNumberingSystems ( alias | ( native*, traditional*, finance*)) >

This element defines general categories of numbering systems that are sometimes used in the given locale for formatting numeric quantities. These additional numbering systems are often used in very specific contexts, such as in calendars or for financial purposes. There are currently three defined categories, as follows:

native
Defines the numbering system used for the native digits, usually defined as a part of the script used to write the language. The native numbering system can only be a numeric positional decimal-digit numbering system, using digits with General_Category=Decimal_Number.
traditional
Defines the traditional numerals for a locale. This numbering system may be numeric or algorithmic. If the traditional numbering system is not defined, applications should use the native numbering system as a fallback.
finance
Defines the numbering system used for financial quantities. This numbering system may be numeric or algorithmic. This is often used for ideographic languages such as Chinese, where it would be easy to alter an amount represented in the default numbering system simply by adding additional strokes. If the financial numbering system is not specified, applications should use the default numbering system as a fallback.

The categories defined for other numbering systems can be used in a Unicode locale identifier to select the proper numbering system without having to know the specific numbering system by name. For example:

For more information on numbering systems and their definitions, see Section 1: Numbering Systems.

2.3 Number Symbols

<!ELEMENT symbols (alias | (decimal*, group*, list*, percentSign*, nativeZeroDigit*, patternDigit*, plusSign*, minusSign*, exponential*, superscriptingExponent*, perMille*, infinity*, nan*, currencyDecimal*, currencyGroup*, timeSeparator*, special*)) >

Number symbols define the localized symbols that are commonly used when formatting numbers in a given locale. These symbols can be referenced using a number formatting pattern as defined in Section 3: Number Format Patterns.

The available number symbols are as follows:

decimal
- separates the integer and fractional part of the number.
group
- separates clusters of integer digits to make large numbers more legible; commonly used for thousands (grouping size 3, e.g. "100,000,000") or in some locales, ten-thousands (grouping size 4, e.g. "1,0000,0000"). There may be two different grouping sizes: The primary grouping size used for the least significant integer group, and the secondary grouping size used for more significant groups; these are not the same in all locales (e.g. "12,34,56,789"). If a pattern contains multiple grouping separators, the interval between the last one and the end of the integer defines the primary grouping size, and the interval between the last two defines the secondary grouping size. All others are ignored, so "#,##,###,####" == "###,###,####" == "##,#,###,####".
list
- separates lists of numbers
percentSign
- symbol used to indicate a percentage (1/100th) amount. (If present, the value is also multiplied by 100 before formatting. That way 1.23 → 123%)
nativeZeroDigit
- Deprecated - do not use.
patternDigit
- Symbol used to indicate any digit value, typically #. When that digit is zero, then it is not shown.
minusSign
- Symbol used to denote negative value.
plusSign
- Symbol used to denote positive value.
exponential
- Symbol separating the mantissa and exponent values.
superscriptingExponent
- (Programmers are used to the fallback exponent style “1.23E4”, but that should not be shown to end-users. Instead, the exponential notation superscriptingExponent should be used to show a format like “1.23 × 104”. ) The superscripting can use markup, such as <sup>4</sup> in HTML, or for the special case of Latin digits, use the superscript characters: U+207B ( ⁻ ), U+2070 ( ⁰ ), U+00B9 ( ¹ ), U+00B2 ( ² ), U+00B3 ( ³ ), U+2074 ( ⁴ ) .. U+2079 ( ⁹ ).
perMille
- symbol used to indicate a per-mille (1/1000th) amount. (If present, the value is also multiplied by 1000 before formatting. That way 1.23 → 1230 [1/000])
infinity
- The infinity sign. Corresponds to the IEEE infinity bit pattern.
nan - Not a number
- The NaN sign. Corresponds to the IEEE NaN bit pattern.
currencyDecimal
- This is used as the decimal separator in currency formatting/parsing, instead of the regular decimal separator. This item is optional in the CLDR.
currencyGroup
- This is used as the grouping separator in currency formatting/parsing, instead of the regular grouping separator. This item is optional in the CLDR.
timeSeparator
- This replaces any use of ":" in a date-time format pattern. This allows the same time format to be used for multiple number systems. For example, the time format for Arabic should be : when using the Latin numbering system (0, 1, 2, …), but a comma when the Arabic numbering system is used (٠‎ - ١‎ - ٢‎ …)

Example:

<symbols>
      <decimal>.</decimal>
      <group>,</group>
      <list>;</list>
      <percentSign>%</percentSign>
      <patternDigit>#</patternDigit>
      <plusSign>+</plusSign>
      <minusSign>-</minusSign>
      <exponential>E</exponential>
      <superscriptingExponent>×</exponential>
      <perMille></perMille>
      <infinity></infinity>
      <nan></nan>
      <timeSeparator>:</timeSeparator>
</symbols>

<!ATTLIST symbols numberSystem CDATA #IMPLIED >
The numberSystem attribute is used to specify that the given number symbols are to be used when the given numbering system is active. Number symbols can only be defined for numbering systems of the "numeric" type, since any special symbols required for an algorithmic numbering system should be specified by the RBNF formatting rules used for that numbering system. By default, number symbols without a specific numberSystem attribute are assumed to be used for the "latn" numbering system, which is western (ASCII) digits. Locales that specify a numbering system other than "latn" as the default should also specify number formatting symbols that are appropriate for use within the context of the given numbering system. For example, a locale that uses the Arabic-Indic digits as its default would likely use an Arabic comma for the grouping separator rather than the ASCII comma.
For more information on numbering systems and their definitions, see Section 1: Numbering Systems.

2.4 Number Formats

<!ELEMENT decimalFormats (alias | (default*, decimalFormatLength*, special*))>
<!ELEMENT decimalFormatLength (alias | (default*, decimalFormat*, special*))>
<!ATTLIST decimalFormatLength type ( full | long | medium | short ) #IMPLIED >
<!ELEMENT decimalFormat (alias | (pattern*, special*)) >

(scientificFormats, percentFormats have the same structure)

Number formats are used to define the rules for formatting numeric quantities using the pattern syntax described in Section 3: Number Format Patterns.

Different formats are provided for different contexts, as follows:

 
decimalFormats
The normal locale specific way to write a base 10 number. Variations of the decimalFormat pattern are provided that allow compact number formatting.
percentFormats
Pattern for use with percentage formatting
scientificFormats
Pattern for use with scientific (exponent) formatting.

Example:

<decimalFormats>
  <decimalFormatLength type="long">
    <decimalFormat>
      <pattern>#,##0.###</pattern>
    </decimalFormat>
  </decimalFormatLength>
</decimalFormats>
<scientificFormats>
  <default type="long"/>
  <scientificFormatLength type="long">
    <scientificFormat>
      <pattern>0.000###E+00</pattern>
    </scientificFormat>
  </scientificFormatLength>
  <scientificFormatLength type="medium">
    <scientificFormat>
      <pattern>0.00##E+00</pattern>
    </scientificFormat>
  </scientificFormatLength>
</scientificFormats>
<percentFormats>
  <percentFormatLength type="long">
    <percentFormat>
      <pattern>#,##0%</pattern>
    </percentFormat>
  </percentFormatLength>
</percentFormats>

<!ATTLIST symbols numberSystem CDATA #IMPLIED >
The numberSystem attribute is used to specify that the given number formatting pattern(s) are to be used when the given numbering system is active. By default, number formatting patterns without a specific numberSystem attribute are assumed to be used for the "latn" numbering system, which is western (ASCII) digits. Locales that specify a numbering system other than "latn" as the default should also specify number formatting patterns that are appropriate for use within the context of the given numbering system.
For more information on numbering systems and their definitions, see Section 1: Numbering Systems.

2.4.1 Compact Number Formats

A pattern type attribute is used for compact number formats, such as the following:
<decimalFormatLength type="long">
<decimalFormat>
<pattern type="1000" count="one">0 millier</pattern>
<pattern type="1000" count="other">0 milliers</pattern>
<pattern type="10000" count="one">00 mille</pattern>
<pattern type="10000" count="other">00 mille</pattern>
<pattern type="100000" count="one">000 mille</pattern>
<pattern type="100000" count="other">000 mille</pattern>
<pattern type="1000000" count="one">0 million</pattern>
<pattern type="1000000" count="other">0 millions</pattern>
...
</decimalFormat>
</decimalFormatLength>
<decimalFormatLength type="short">
<decimalFormat>
<pattern type="1000" count="one">0 K</pattern>
<pattern type="1000" count="other">0 K</pattern>
<pattern type="10000" count="one">00 K</pattern>
<pattern type="10000" count="other">00 K</pattern>
<pattern type="100000" count="one">000 K</pattern>
<pattern type="100000" count="other">000 K</pattern>
<pattern type="1000000" count="one">0 M</pattern>
<pattern type="1000000" count="other">0 M</pattern>
...
</decimalFormat>

To format a number N, the greatest type less than or equal to N is used, with the appropriate plural category. N is divided by the type, after removing the number of zeros in the pattern, less 1. APIs supporting this format should provide control over the number of significant or fraction digits.

Thus N=12345 matches <pattern type="10000" count="other">00 K</pattern> . N is divided by 1000 (obtained from10000 after removing "00" and restoring one "0". The result is formatted according to the normal decimal pattern. With no fractional digits, that yields "12 K".

The short format is designed for UI environments where space is at a premium, and should ideally result in a formatted string no more than about 6 em wide (with no fractional digits).

2.4.2 Currency Formats

Pattern for use with currency formatting. This format contains a few additional structural options that allow proper placement of the currency symbol relative to the numeric quantity. Refer to Section 4 - Currencies for additional information on the use of these options.

<!ELEMENT currencyFormats (alias | (default*, currencySpacing*, currencyFormatLength*, unitPattern*, special*)) >
<!ELEMENT currencySpacing (alias | (beforeCurrency*, afterCurrency*, special*)) >
<!ELEMENT beforeCurrency (alias | (currencyMatch*, surroundingMatch*, insertBetween*)) >
<!ELEMENT afterCurrency (alias | (currencyMatch*, surroundingMatch*, insertBetween*)) >
<!ELEMENT currencyMatch ( #PCDATA ) >
<!ELEMENT surroundingMatch ( #PCDATA )) >
<!ELEMENT insertBetween ( #PCDATA ) >
<!ELEMENT currencyFormatLength (alias | (default*, currencyFormat*, special*)) >
<!ATTLIST currencyFormatLength type ( full | long | medium | short ) #IMPLIED >
<!ELEMENT currencyFormat (alias | (pattern*, special*)) >

In addition to a standard currency format, in which negative currency amounts might typically be displayed as something like “-$3.27”, locales may provide an "accounting" form, in which for "en_US" the same example would appear as “($3.27)”.

<currencyFormats>
  <currencyFormatLength>
    <currencyFormat type="standard">
      <pattern>¤#,##0.00</pattern>
    </currencyFormat>
    <currencyFormat type="accounting">
      <pattern>¤#,##0.00;(¤#,##0.00)</pattern>
    </currencyFormat>
  </currencyFormatLength>
</currencyFormats>

2.5 Miscellaneous Patterns

<!ELEMENT miscPatterns (alias | (default*, pattern*, special*)) >
<!ATTLIST miscPatterns numberSystem CDATA #IMPLIED >

The miscPatterns supply additional patterns for special purposes. The currently defined values are:

atLeast
indicates a number or higher, such as: “99+” to indicate that there are 99 items or more.
range
indicates a range of numbers, such as: “99–103” to indicate that there are from 99 to 103 items.

For example:

<miscPatterns numberSystem="…">
  <pattern type="atLeast">⩾{0}</pattern>
  <pattern type="range">{0}–{1}</pattern>
</miscPatterns>

3 Number Format Patterns

3.1 Number Patterns

Number patterns affect how numbers are interpreted in a localized context. Here are some examples, based on the French locale. The "." shows where the decimal point should go. The "," shows where the thousands separator should go. A "0" indicates zero-padding: if the number is too short, a zero (in the locale's numeric set) will go there. A "#" indicates no padding: if the number is too short, nothing goes there. A "¤" shows where the currency sign will go. The following illustrates the effects of different patterns for the French locale, with the number "1234.567". Notice how the pattern characters ',' and '.' are replaced by the characters appropriate for the locale.

Pattern Currency Text
#,##0.## n/a 1 234,57
#,##0.### n/a 1 234,567
###0.##### n/a 1234,567
###0.0000# n/a 1234,5670
00000.0000 n/a 01234,5670
#,##0.00 ¤ EUR 1 234,57 €
JPY 1 235 ¥JP

The number of # placeholder characters before the decimal do not matter, since no limit is placed on the maximum number of digits. There should, however, be at least one zero someplace in the pattern. In currency formats, the number of digits after the decimal also do not matter, since the information in the supplemental data (see Supplemental Currency Data) is used to override the number of decimal places — and the rounding — according to the currency that is being formatted. That can be seen in the above chart, with the difference between Yen and Euro formatting.

When parsing using a pattern, a lenient parse should be used; see Lenient Parsing.

3.2 Special Pattern Characters

Many characters in a pattern are taken literally; they are matched during parsing and output unchanged during formatting. Special characters, on the other hand, stand for other characters, strings, or classes of characters. For example, the '#' character is replaced by a localized digit. Often the replacement character is the same as the pattern character; in the U.S. locale, the ',' grouping character is replaced by ','. However, the replacement is still happening, and if the symbols are modified, the grouping character changes. Some special characters affect the behavior of the formatter by their presence; for example, if the percent character is seen, then the value is multiplied by 100 before being displayed.

To insert a special character in a pattern as a literal, that is, without any special meaning, the character must be quoted. There are some exceptions to this which are noted below.

Symbol Location Localized? Meaning
0 Number Yes Digit
1-9 Number Yes '1' through '9' indicate rounding.
@ Number No Significant digit
# Number Yes Digit, zero shows as absent
. Number Yes Decimal separator or monetary decimal separator
- Number Yes Minus sign
, Number Yes Grouping separator. May occur in both the integer part and the fractional part. The position determines the grouping.
E Number Yes Separates mantissa and exponent in scientific notation. Need not be quoted in prefix or suffix.
+ Exponent Yes Prefix positive exponents with localized plus sign. Need not be quoted in prefix or suffix.
; Subpattern boundary Yes Separates positive and negative subpatterns
% Prefix or suffix Yes Multiply by 100 and show as percentage

(U+2030)
Prefix or suffix Yes Multiply by 1000 and show as per mille
¤ (U+00A4) Prefix or suffix No Currency sign, replaced by currency symbol. If doubled, replaced by international currency symbol. If tripled, uses the long form of the decimal symbol. If present in a pattern, the monetary decimal separator and grouping separators (if available) are used instead of the numeric ones.
' Prefix or suffix No Used to quote special characters in a prefix or suffix, for example, "'#'#" formats 123 to "#123". To create a single quote itself, use two in a row: "# o''clock".
* Prefix or suffix boundary Yes Pad escape, precedes pad character

A pattern contains a positive and may contain a negative subpattern, for example, "#,##0.00;(#,##0.00)". Each subpattern has a prefix, a numeric part, and a suffix. If there is no explicit negative subpattern, the negative subpattern is the localized minus sign prefixed to the positive subpattern. That is, "0.00" alone is equivalent to "0.00;-0.00". If there is an explicit negative subpattern, it serves only to specify the negative prefix and suffix; the number of digits, minimal digits, and other characteristics are ignored in the negative subpattern. That means that "#,##0.0#;(#)" has precisely the same result as "#,##0.0#;(#,##0.0#)".

Note: The thousands separator and decimal separator in this pattern are always ',' and '.'. They are substituted by the code with the correct local values according to other fields in CLDR.

The prefixes, suffixes, and various symbols used for infinity, digits, thousands separators, decimal separators, and so on may be set to arbitrary values, and they will appear properly during formatting. However, care must be taken that the symbols and strings do not conflict, or parsing will be unreliable. For example, either the positive and negative prefixes or the suffixes must be distinct for any parser using this data to be able to distinguish positive from negative values. Another example is that the decimal separator and thousands separator should be distinct characters, or parsing will be impossible.

The grouping separator is a character that separates clusters of integer digits to make large numbers more legible. It is commonly used for thousands, but in some locales it separates ten-thousands. The grouping size is the number of digits between the grouping separators, such as 3 for "100,000,000" or 4 for "1 0000 0000". There are actually two different grouping sizes: One used for the least significant integer digits, the primary grouping size, and one used for all others, the secondary grouping size. In most locales these are the same, but sometimes they are different. For example, if the primary grouping interval is 3, and the secondary is 2, then this corresponds to the pattern "#,##,##0", and the number 123456789 is formatted as "12,34,56,789". If a pattern contains multiple grouping separators, the interval between the last one and the end of the integer defines the primary grouping size, and the interval between the last two defines the secondary grouping size. All others are ignored, so "#,##,###,####" == "###,###,####" == "##,#,###,####".

The grouping separator may also occur in the fractional part, such as in “#,##0.###,#”. This is most commonly done where the grouping separator character is a thin, non-breaking space (U+202F), such as “1.618 033 988 75”. See physics.nist.gov/cuu/Units/checklist.html.

For consistency in the CLDR data, the following conventions

3.3 Formatting

Formatting is guided by several parameters, all of which can be specified either using a pattern or using an external API designed for number formatting. The following description applies to formats that do not use scientific notation or significant digits.

Special Values

NaN is represented as a single character, typically (U+FFFD) . This character is determined by the localized number symbols. This is the only value for which the prefixes and suffixes are not used.

Infinity is represented as a single character, typically (U+221E) , with the positive or negative prefixes and suffixes applied. The infinity character is determined by the localized number symbols.

3.4 Scientific Notation

Numbers in scientific notation are expressed as the product of a mantissa and a power of ten, for example, 1234 can be expressed as 1.234 x 103. The mantissa is typically in the half-open interval [1.0, 10.0) or sometimes [0.0, 1.0), but it need not be. In a pattern, the exponent character immediately followed by one or more digit characters indicates scientific notation. Example: "0.###E0" formats the number 1234 as "1.234E3".

3.5 Significant Digits

There are two ways of controlling how many digits are shows: (a) significant digits counts, or (b) integer and fraction digit counts. Integer and fraction digit counts are described above. When a formatter is using significant digits counts, it uses however many integer and fraction digits are required to display the specified number of significant digits. It may ignore min/max integer/fraction digits, or it may use them to the extent possible.

Examples:

Pattern Minimum significant digits Maximum significant digits Number Output
@@@ 3 3 12345 12300
@@@ 3 3 0.12345 0.123
@@## 2 4 3.14159 3.142
@@## 2 4 1.23004 1.23

3.6 Padding

Patterns support padding the result to a specific width. In a pattern the pad escape character, followed by a single pad character, causes padding to be parsed and formatted. The pad escape character is '*'. For example, "$*x#,##0.00" formats 123 to "$xx123.00" , and 1234 to "$1,234.00" .

3.7 Rounding

Patterns support rounding to a specific increment. For example, 1230 rounded to the nearest 50 is 1250. Mathematically, rounding to specific increments is performed by dividing by the increment, rounding to an integer, then multiplying by the increment. To take a more bizarre example, 1.234 rounded to the nearest 0.65 is 1.3, as follows:

Original: 1.234
Divide by increment (0.65): 1.89846...
Round: 2
Multiply by increment (0.65): 1.3

To specify a rounding increment in a pattern, include the increment in the pattern itself. "#,#50" specifies a rounding increment of 50. "#,##0.05" specifies a rounding increment of 0.05.

3.8 Quoting Rules

Single quotes, ('), enclose bits of the pattern that should be treated literally. Inside a quoted string, two single quotes ('') are replaced with a single one ('). For example: 'X '#' Q ' -> X 1939 Q (Literal strings underlined.)

4 Currencies

<!ELEMENT currencies (alias | (default?, currency*, special*)) >
<!ELEMENT currency (alias | (((pattern+, displayName*, symbol*) | (displayName+, symbol*, pattern*) | (symbol+, pattern*))?, decimal*, group*, special*)) >
<!ELEMENT symbol ( #PCDATA ) >
<!ATTLIST symbol choice ( true | false ) #IMPLIED > <!-- deprecated -->

Note: The term "pattern" appears twice in the above. The first is for consistency with all other cases of pattern + displayName; the second is for backwards compatibility.

<currencies>
    <currency type="USD">
        <displayName>Dollar</displayName>
        <symbol>$</symbol>
    </currency>
    <currency type ="JPY">
        <displayName>Yen</displayName>
        <symbol>¥</symbol>
    </currency>
    <currency type="PTE">
        <displayName>Escudo</displayName>
        <symbol>$</symbol>
    </currency>
</currencies>

In formatting currencies, the currency number format is used with the appropriate symbol from <currencies>, according to the currency code. The <currencies> list can contain codes that are no longer in current use, such as PTE. The choice attribute has been deprecated.

The count attribute distinguishes the different plural forms, such as in the following:

<currencyFormats>
    <unitPattern count="other">{0} {1}</unitPattern>
    ...
<currencies>
<currency type="ZWD">
    <displayName>Zimbabwe Dollar</displayName>
    <displayName count="one">Zimbabwe dollar</displayName>
    <displayName count="other">Zimbabwe dollars</displayName>
    <symbol>Z$</symbol>
</currency>

To format a particular currency value "ZWD" for a particular numeric value n:

  1. First see if there is a count with an explicit number (0 or 1). If so, use that string.
  2. Otherwise, determine the count value that corresponds to n using the rules in Section 5 - Language Plural Rules
  3. Next, get the currency unitPattern.
    1. Look for a unitPattern element that matches the count value, starting in the current locale and then following the locale fallback chain up to, but not including root.
    2. If no matching unitPattern element was found in the previous step, then look for a unitPattern element that matches count="other", starting in the current locale and then following the locale fallback chain up to root (which has a unitPattern element with count="other" for every unit type).
    3. The resulting unitPattern element indicates the appropriate positioning of the numeric value and the currency display name.
  4. Next, get the displayName element for the currency.
    1. Look for a displayName element that matches the count value, starting in the current locale and then following the locale fallback chain up to, but not including root.
    2. If no matching displayName element was found in the previous step, then look for a displayName element that matches count="other", starting in the current locale and then following the locale fallback chain up to, but not including root.
    3. If no matching displayName element was found in the previous step, then look for a displayName element that with no count, starting in the current locale and then following the locale fallback chain up to root.
    4. If there is no displayName element, use the currency code itself (for example, "ZWD").
  5. The numeric value, formatted according to the locale with the number of decimals appropriate for the currency, is substituted for {0} in the unitPattern, while the currency display name is substituted for the {1}.

While for English this may seem overly complex, for some other languages different plural forms are used for different unit types; the plural forms for certain unit types may not use all of the plural-form tags defined for the language.

For example, if the the currency is ZWD and the number is 1234, then the latter maps to count="other" for English. The unit pattern for that is "{0} {1}", and the display name is "Zimbabwe dollars". The final formatted number is then "1,234 Zimbabwe dollars".

When the currency symbol is substituted into a pattern, there may be some further modifications, according to the following.

<currencySpacing>
  <beforeCurrency>
    <currencyMatch>[:letter:]</currencyMatch>
    <surroundingMatch>[:digit:]</surroundingMatch>
    <insertBetween>&#x00a0;</insertBetween>
  </beforeCurrency>
  <afterCurrency>
    <currencyMatch>[:letter:]</currencyMatch>
    <surroundingMatch>[:digit:]</surroundingMatch>
    <insertBetween>&#x00a0;</insertBetween>
  </afterCurrency>
</currencySpacing>

This element controls whether additional characters are inserted on the boundary between the symbol and the pattern. For example, with the above currencySpacing, inserting the symbol "US$" into the pattern "#,##0.00¤" would result in an extra no-break space inserted before the symbol, for example, "#,##0.00 US$". The beforeCurrency element governs this case, since we are looking before the "¤" symbol. The currencyMatch is positive, since the "U" in "US$" is at the start of the currency symbol being substituted. The surroundingMatch is positive, since the character just before the "¤" will be a digit. Because these two conditions are true, the insertion is made.

Conversely, look at the pattern "¤#,##0.00" with the symbol "US$". In this case, there is no insertion; the result is simply "US$#,##0.00". The afterCurrency element governs this case, since we are looking after the "¤" symbol. The surroundingMatch is positive, since the character just after the "¤" will be a digit. However, the currencyMatch is not positive, since the "$" in "US$" is at the end of the currency symbol being substituted. So the insertion is not made.

For more information on the matching used in the currencyMatch and surroundingMatch elements, see the main document Appendix E: Unicode Sets.

Currencies can also contain optional grouping, decimal data, and pattern elements. This data is inherited from the <symbols> in the same locale data (if not present in the chain up to root), so only the differing data will be present. See the main document Section 4.1 Multiple Inheritance.

Note: Currency values should never be interchanged without a known currency code. You never want the number 3.5 interpreted as $3.50 by one user and €3.50 by another. Locale data contains localization information for currencies, not a currency value for a country. A currency amount logically consists of a numeric value, plus an accompanying currency code (or equivalent). The currency code may be implicit in a protocol, such as where USD is implicit. But if the raw numeric value is transmitted without any context, then it has no definitive interpretation.

Notice that the currency code is completely independent of the end-user's language or locale. For example, BGN is the code for Bulgarian Lev. A currency amount of <BGN, 1.23456×10³> would be localized for a Bulgarian user into "1 234,56 лв." (using Cyrillic letters). For an English user it would be localized into the string "BGN 1,234.56" The end-user's language is needed for doing this last localization step; but that language is completely orthogonal to the currency code needed in the data. After all, the same English user could be working with dozens of currencies. Notice also that the currency code is also independent of whether currency values are inter-converted, which requires more interesting financial processing: the rate of conversion may depend on a variety of factors.

Thus logically speaking, once a currency amount is entered into a system, it should be logically accompanied by a currency code in all processing. This currency code is independent of whatever the user's original locale was. Only in badly-designed software is the currency code (or equivalent) not present, so that the software has to "guess" at the currency code based on the user's locale.

Note: The number of decimal places and the rounding for each currency is not locale-specific data, and is not contained in the Locale Data Markup Language format. Those values override whatever is given in the currency numberFormat. For more information, see Supplemental Currency Data.

For background information on currency names, see [CurrencyInfo].

4.1 Supplemental Currency Data

<!ELEMENT currencyData ( fractions*, region+ ) >
<!ELEMENT fractions ( info+ ) >

<!ELEMENT info EMPTY >
<!ATTLIST info iso4217 NMTOKEN #REQUIRED >
<!ATTLIST info digits NMTOKEN #IMPLIED >
<!ATTLIST info rounding NMTOKEN #IMPLIED >
<!ATTLIST info cashDigits NMTOKEN #IMPLIED >
<!ATTLIST info cashRounding NMTOKEN #IMPLIED >

<!ELEMENT region ( currency* ) >
<!ATTLIST region iso3166 NMTOKEN #REQUIRED >

<!ELEMENT currency ( alternate* ) >
<!ATTLIST currency from NMTOKEN #IMPLIED >
<!ATTLIST currency to NMTOKEN #IMPLIED >
<!ATTLIST currency iso4217 NMTOKEN #REQUIRED >
<!ATTLIST currency tender ( true | false ) #IMPLIED >

Each currencyData element contains one fractions element followed by one or more region elements. Here is an example for illustration.

<supplementalData>
  <currencyData>
    <fractions>
      ...
      <info iso4217="CHF" digits="2" rounding="5"/>
      ...
      <info iso4217="ITL" digits="0"/>
      ...
    </fractions>
    ...
    <region iso3166="IT">
      <currency iso4217="EUR" from="1999-01-01"/>
      <currency iso4217="ITL" from="1862-8-24" to="2002-02-28"/>
    </region>
    ...
    <region iso3166="CS">
      <currency iso4217="EUR" from="2003-02-04"/>
      <currency iso4217="CSD" from="2002-05-15"/>
      <currency iso4217="YUM" from="1994-01-24" to="2002-05-15"/>
    </region>
    ...
  </currencyData>
...
</supplementalData>

The fractions element contains any number of info elements, with the following attributes:

For example, the following line

    <info iso4217="CZK" digits="2" rounding="0"/>

should cause the value 2.006 to be displayed as “2.01”, not “2.00”.

Each region element contains one attribute:

And can have any number of currency elements, with the ordered subelements.

    <region iso3166="IT"> <!-- Italy -->
      <currency iso4217="EUR" from="2002-01-01"/>
      <currency iso4217="ITL" to="2001-12-31"/>
    </region>

That is, each currency element will list an interval in which it was valid. The ordering of the elements in the list tells us which was the primary currency during any period in time. Here is an example of such an overlap:

<currency iso4217="CSD" to="2002-05-15"/>
<currency iso4217="YUD" from="1994-01-24" to="2002-05-15"/>
<currency iso4217="YUN" from="1994-01-01" to="1994-07-22"/>

The from element is limited by the fact that ISO 4217 does not go very far back in time, so there may be no ISO code for the previous currency.

Currencies change relatively frequently. There are different types of changes:

  1. YU=>CS (name change)
  2. CS=>RS+ME (split, different names)
  3. SD=>SD+SS (split, same name for one // South Sudan splits from Sudan)
  4. DE+DD=>DE (Union, reuses one name // East Germany unifies with Germany)

The UN Information  is used to determine dates due to country changes.

When a code is no longer in use, it is terminated (see #1, #2, #4, #5)

Example:

When codes split, each of the new codes inherits (see #2, #3) the previous data. However, some modifications can be made if it is clear that currencies were only in use in one of the parts.

When codes merge, the data is copied from the most populous part.

Example. When CS split into RS and ME:

5 Language Plural Rules

<!ELEMENT plurals (pluralRules*, pluralRanges*) >
<!ATTLIST plurals type ( ordinal | cardinal ) #IMPLIED > <!-- default is cardinal -->

<!ELEMENT pluralRules (pluralRule*) >
<!ATTLIST pluralRules locales NMTOKENS #REQUIRED >

<!ELEMENT pluralRule ( #PCDATA ) >
<!ATTLIST pluralRule count (zero | one | two | few | many | other) #REQUIRED >

The plural categories are used to format messages with numeric placeholders, expressed as decimal numbers. The fundamental rule for determining plural categories is the existence of minimal pairs: whenever two different numbers may require different versions of the same message, then the numbers have different plural categories.

This happens even if nouns are invariant; even if all English nouns were invariant (like “sheep”), English would still require 2 plural categories because of subject-verb agreement, and pronoun agreement. For example:

  1. 1 sheep is here. Do you want to buy it?
  2. 2 sheep are here. Do you want to buy them?

For more information, see Determining-Plural-Categories.

English does not have a separate plural category for “zero”, because it does not require a different message for “0”. For example, the same message can be used below, with just the numeric placeholder changing.

  1. You have 3 friends online.

  2. You have 0 friends online.

However, across many languages it is commonly more natural to express "0" messages with a negative (“None of your friends are online.”) and "1" messages also with an alternate form “You have a friend online.”. Thus pluralized message APIs should also offer the ability to specify at least the 0 and 1 cases explicitly; developers can use that ability whenever these values might occur in a placeholder.

This section defines the types of plural forms that exist in a language—namely, the cardinal and ordinal plural forms. Cardinal plural forms express units such as time, currency or distance, used in conjunction with a number expressed in decimal digits (i.e. "2", not "two", and not an indefinite number such as "some" or "many"). Ordinal plural forms denote the order of items in a set and are always integers. For example, English has two forms for cardinals:

and four forms for ordinals:

Other languages may have additional forms or only one form for each type of plural. CLDR provides the following tags for designating the various plural forms of a language; for a given language, only the tags necessary for that language are defined, along with the specific numeric ranges covered by each tag (for example, the plural form "few" may be used for the numeric range 2–4 in one language and 3–9 in another):

In addition, an "other" tag is always implicitly defined to cover the forms not explicitly designated by the tags defined for a language. This "other" tag is also used for languages that only have a single form (in which case no plural-form tags are explicitly defined for the language). For a more complex example, consider the cardinal rules for Russian and certain other languages:

<pluralRules locales="hr ru sr uk">
	<pluralRules count="one">n mod 10 is 1 and n mod 100 is not 11</pluralRule>
	<pluralRules count="few">n mod 10 in 2..4 and n mod 100 not in 12..14</pluralRule>
</pluralRules>

These rules specify that Russian has a "one" form (for 1, 21, 31, 41, 51, …), a "few" form (for 2–4, 22–24, 32–34, …), and implicitly an "other" form (for everything else: 0, 5–20, 25–30, 35–40, …, decimals). Russian does not need additional separate forms for zero, two, or many, so these are not defined.

Plural categories may also differ according to the decimals. For example, here are some of the behaviors exhibited by different languages:

Behavior Description Example
Base The fractions are ignored; the category is the same as the category of the integer. 1.13 has the same plural category as 1.
Separate All fractions by value are in one category (typically ‘other’ = ‘plural’). 1.01 gets the same class as 9;
1.00 gets the same category as 1.
Visible All visible fractions are in one category (typically ‘other’ = ‘plural). 1.00, 1.01, 3.5 all get the same category.
Digits The visible fraction determines the category. 1.13 gets the same class as 13.

There are also variants of the above: for example, short fractions may have the Digits behavior, but longer fractions may just look at the final digit of the fraction.

5.1 Plural rules syntax

The xml value for each pluralRule is a condition with a boolean result that specifies whether that rule (i.e. that plural form) applies to a given numeric value n, where n can be expressed as a decimal fraction. Clients of CLDR may express all the rules for a locale using the following syntax:

rules         = rule (';' rule)*
rule          = keyword ':' condition samples
              | 'other' ':' samples
keyword       = [a-z]+
keyword       = [a-z]+

In CLDR, the keyword is the attribute value of 'count'. Those values in CLDR are currently limited to just what is in the DTD, but clients may support other values.

The conditions themselves have the following syntax.

condition     = and_condition ('or' and_condition)*
samples       = ('@integer' sampleList)?
                ('@decimal' sampleList)?                 and_condition = relation ('and' relation)*
relation      = is_relation | in_relation | within_relation
is_relation   = expr 'is' ('not')? value
in_relation   = expr (('not')? 'in' | '=' | '!=') range_list
within_relation = expr ('not')? 'within' range_list
expr          = operand (('mod' | '%') value)? operand = 'n' | 'i' | 'f' | 't' | 'v' | 'w'
range_list    = (range | value) (',' range_list)*
range         = value'..'value sampleList = sampleRange (',' sampleRange)* (',' ('…'|'...'))? sampleRange = decimalValue '~' decimalValue value         = digit+ decimalValue = value ('.' value)?
digit         = 0|1|2|3|4|5|6|7|8|9

5.1.1 Operands

The operands have the following meaning:

Symbol Value
n absolute value of the source number (integer and decimals).
i integer digits of n.
v number of visible fraction digits in n, with trailing zeros.
w number of visible fraction digits in n, without trailing zeros.
f visible fractional digits in n, with trailing zeros.
t visible fractional digits in n, without trailing zeros.

Example values:

n
i
v
w
f
t
1
1
0
0
0
0
1.0
1
1
0
0
0
1.00
1
2
0
0
0
1.3
1
1
1
3
3
1.30
1
2
1
30
3
1.03
1
2
2
3
3
1.230
1
3
2
230
23

5.1.2 Relations

The keywords 'mod', 'in', 'is', and 'within' are present only for backwards compatibility. The preferred form is to use '%' for modulo, and '=' or '!=' for the relations, with the operand 'i' instead of within. The difference between in and within is that in only includes integers in the specified range, while within includes all values.

The relations can take comma-separated lists, such as: n in 3,5,7..15.

The modulus (% or mod) is a remainder operation as defined in Java; for example, where n = 4.3 the result of n mod 3 is 1.3.

The values of relations are defined according to the operand as follows. Importantly, the results may depend on the decimals in the source, including trailing zeros.

  1. Let the base value BV be computed from absolute value of the original source number according to the operand.
  2. Let R be false when the comparison contains ‘not’.
  3. Let R be !R if  the comparison contains ‘within’ and the source number is not an integer.
  4. If there is a module value MV, let BV be BV - floor(BV/MV).
  5. Let CR be the list of comparison ranges, normalized that overlapping ranges are merged. Single values in the rule are represented by a range with identical <starti, endi> values.
  6. Iterate through CR:
    • if starti ≤ BV ≤ endi then return R.
  7. Otherwise return !R.

Example Rules:

Rules Comments
one: n = 1
few: n = 2..4
This defines two rules, for 'one' and 'few'. The condition for 'one' is "n = 1" which means that the number must be equal to 1 for this condition to pass. The condition for 'few' is "n = 2..4" which means that the number must be between 2 and 4 inclusive for this condition to pass. All other numbers are assigned the keyword 'other' by the default rule.
zero: n = 0 or n != 1 and n mod 100 = 1..19
one: n = 1
Each rule must not overlap with other rules. Also note that a modulus is applied to n in the last rule, thus its condition holds for 119, 219, 319...
one: n = 1
few: n mod 10 = 2..4 and n mod 100 != 12..14
This illustrates conjunction and negation. The condition for 'few' has two parts, both of which must be met: "n mod 10 = 2..4" and "n mod 100 != 12..14". The first part applies a modulus to n before the test as in the previous example. The second part applies a different modulus and also uses negation, thus it matches all numbers not in 12, 13, 14, 112, 113, 114, 212, 213, 214...

5.1.3 Samples

Samples are provided if sample indicator (@integer or @decimal) is present on any rule. (CLDR always provides samples.)

Where samples are provided, the absence of one of the sample indicators indicates that no numeric values can satisify that rule. For example, the rule "i = 1 and v = 0" can only have integer samples, so @decimal must not occur.

The sampleRanges have a special notation: start~end. The start and end values must have the same number of decimal digits. The range encompasses all and only values those value v where start ≤ v ≤ end, and where v has the same number of decimal places as start and end.

Samples must indicate whether they are infinite or not. The '…' marker must be present if and only infinitely many values (integer or decimal) can satisfy the rule. If a set is not infinite, it must list all the possible values.

Rules Comments
@integer 1, 3~5 1, 3, 4, 5.
@integer 3~5, 103~105, … Infinite set: 3, 4, 5, 103, 104, 105, …
@decimal 1.3~1.5, 1.03~1.05, … Infinite set: 1.3, 1.4, 1.5, 1.03, 1.04, 1.05, …

In determining whether a set of samples is infinite, leading zero integer digits and trailing zero decimals are not significant. Thus "i = 1 and f = 0" is satisfied by 01, 1, 1.0, 1.00, 1.000, etc. but is still considered finite.

5.1.4 Using Cardinals

Elements such as <currencyFormats>, <currency> and <unit> provide selection among subelements designating various localized cardinal plural forms by tagging each of the relevant subelements with a different count value, or with no count value in some cases. Note that the plural forms for a specific currencyFormat, unit type, or currency type may not use all of the different plural-form tags defined for the language. To format a currency or unit type for a particular numeric value, determine the count value according to the plural rules for the language, then select the appropriate display form for the currency format, currency type or unit type using the rules in those sections:

5.2 Plural Ranges

<!ELEMENT pluralRanges (pluralRange*) >
<!ATTLIST pluralRanges locales NMTOKENS #REQUIRED >

<!ELEMENT pluralRange ( #PCDATA ) >
<!ATTLIST pluralRange start (zero|one|two|few|many|other) #IMPLIED >
<!ATTLIST pluralRange end (zero|one|two|few|many|other) #IMPLIED >
<!ATTLIST pluralRange result (zero|one|two|few|many|other) #REQUIRED >

Often ranges of numbers are presented to users, such as in “Length: 3.2–4.5 centimeters”. This means any length from 3.2 cm to 4.5 cm, inclusive. However, different languages have different conventions for the pluralization given to a range: should it be “0–1 centimeter” or “0–1 centimeters”? This becomes much more complicated for languages that have many different plural forms, such as Russian or Arabic.

The pluralRanges element provides information allowing an implementation to derive the plural category of a range from the plural categories of the start and end values. If there is no value for a <start,end> pair, the default result is end. However, where that result has been verified for a given language, it is included in the CLDR data.

The data has been gathered presuming that in any usage, the start value is strictly less than the end value, and that no values are negative. Results for any cases that do not meet these criteria are undefined.

6 Rule-Based Number Formatting

<!ELEMENT rbnf ( alias | rulesetGrouping*) >

<!ELEMENT rulesetGrouping ( alias | ruleset*) >
<!ATTLIST rulesetGrouping type NMTOKEN #REQUIRED>

<!ELEMENT ruleset ( alias | rbnfrule*) >
<!ATTLIST ruleset type NMTOKEN #REQUIRED>
<!ATTLIST ruleset access ( public | private ) #IMPLIED >

<!ELEMENT rbnfrule ( #PCDATA ) >
<!ATTLIST rbnfrule value CDATA #REQUIRED >
<!ATTLIST rbnfrule radix CDATA #IMPLIED >
<!ATTLIST rbnfrule decexp CDATA #IMPLIED >

The rule-based number format (RBNF) encapsulates a set of rules for mapping binary numbers to and from a readable representation. They are typically used for spelling out numbers, but can also be used for other number systems like roman numerals, Chinese numerals, or for ordinal numbers (1st, 2nd, 3rd,...).

Where, however, the CLDR plurals or ordinals can be used, their usage is recommended in preference to the RBNF data. First, the RBNF data is not completely fleshed out over all languages that otherwise have modern coverage. Secondly, the alternate forms are neither complete, nor useful without additional information. For example, for German there is spellout-cardinal-masculine, and spellout-cardinal-feminine. But a complete solution would have all genders (masculine/feminine/neuter), all cases (nominative, accusative, dative, genitive), plus context (with strong or weak determiner or none). Moreover, even for the alternate forms that do exist, CLDR does not supply any data for when to use one vs another (eg, when to use spellout-cardinal-masculine vs spellout-cardinal-feminine). So these data are inappropriate for general purpose software.

There are 4 common spellout rules. Some languages may provide more than these 4 types:

In addition to the spellout rules, there are also a numbering system rules. Even though they may be derived from a specific culture, they are typically not translated and the rules are in root. An example of these rules are the Roman numerals where the value 8 comes out as VIII.

With regards to the number range supported for all these number types, the largest possible number range tries to be supported, but some languages may not have words for large numbers. For example, the old Roman numbering system can't support the value 5000 and beyond. For those unsupported cases, the default number format from CLDR is used.

Any rules marked as private should never be referenced externally. Frequently they only support a subrange of numbers that are used in the public rules.

The syntax used in the CLDR representation of rules is intended to be simply a transcription of ICU based RBNF rules into an XML compatible syntax. The rules are fairly sophisticated; for details see Rule-Based Number Formatter [RBNF].

<ruleSetGrouping>

Used to group rules into functional sets for use with ICU. Currently, the valid types of rule set groupings are "SpelloutRules", "OrdinalRules", and "NumberingSystemRules".

<ruleset>

This element denotes a specific rule set to the number formatter. The ruleset is assumed to be a public ruleset unless the attribute type="private" is specified.

<rule>

Contains the actual formatting rule for a particular number or sequence of numbers. The "value" attribute is used to indicate the starting number to which the rule applies. The actual text of the rule is identical to the ICU syntax, with the exception that Unicode left and right arrow characters are used to replace < and > in the rule text, since < and > are reserved characters in XML. The "radix" attribute is used to indicate an alternate radix to be used in calculating the prefix and postfix values for number formatting. Alternate radix values are typically used for formatting year numbers in formal documents, such as "nineteen hundred seventy-six" instead of "one thousand nine hundred seventy-six".

7 Parsing Numbers

The following elements are relevant to determining the value of a parsed number:

Other characters should either be ignored, or indicate the end of input, depending on the application. The key point is to disambiguate the sets of characters that might serve in more than one position, based on context. For example, a period might be either the decimal separator, or part of a currency symbol (for example, "NA f."). Similarly, an "E" could be an exponent indicator, or a currency symbol (the Swaziland Lilangeni uses "E" in the "en" locale). An apostrophe might be the decimal separator, or might be the grouping separator.

Here is a set of heuristic rules that may be helpful: