# Currency Amount (US Format) Key: `finance.currency.amount` Currency amount with US/international formatting: optional currency symbol prefix ($, £, ¥, etc.), optional negative sign or parentheses for negative, comma thousands separator, period decimal separator. Examples: $1,234.56, -$999.99, £10,000.00, $0.50, ¥1,000 Page: Samples: `$1,234.56`, `-$999.99`, `£10,000.00`, `$0.50`, `¥1,000`, `$42.00`, `$1,000,000.00`, `£250.75`, `($1,234.56)`, `($999.99)` ## Background ### Origin FineType defines finance.currency.amount as a currency amount with an optional currency symbol in front, a comma as the thousands separator and a period as the decimal separator.[[1]](https://github.com/meridian-online/finetype/blob/main/labels/definitions_finance.yaml) FineType's definition accepts a negative amount written either with a minus sign or in parentheses.[[1]](https://github.com/meridian-online/finetype/blob/main/labels/definitions_finance.yaml) FineType keeps the inverted convention, with a comma for decimals, as a separate type, finance.currency.amount\_comma.[[1]](https://github.com/meridian-online/finetype/blob/main/labels/definitions_finance.yaml) In the United States, the full stop or period is used as the standard decimal separator.[[2]](https://en.wikipedia.org/wiki/Decimal_separator) Traditionally, English-speaking countries other than South Africa used commas as the delimiter between groups of digits, as in 10,000.[[2]](https://en.wikipedia.org/wiki/Decimal_separator) In Britain the British Standards Institution and some sectors of industry advocated the decimal comma, while the Decimal Currency Board advocated the point.[[2]](https://en.wikipedia.org/wiki/Decimal_separator) In Britain the decimal point was chosen by the Ministry of Technology in 1968.[[2]](https://en.wikipedia.org/wiki/Decimal_separator) Wikipedia records 1,234,567.89 or 1,234,567·89 as the style seen in Ireland, Israel, Japan, Korea, Malaysia, the Philippines, Singapore, Taiwan, Thailand, the United Kingdom and the United States.[[2]](https://en.wikipedia.org/wiki/Decimal_separator) For currencies in English-speaking countries and in most of Latin America, the currency symbol is placed before the amount, as in $20.50.[[3]](https://en.wikipedia.org/wiki/Currency_symbol) In most other countries, including many in Europe and Francophone Canada, the symbol is placed after the amount, as in 20,50 €.[[3]](https://en.wikipedia.org/wiki/Currency_symbol) Unicode's CLDR number specification gives ¤\#,\#\#0.00 as its example of a standard currency format pattern.[[4]](https://www.unicode.org/reports/tr35/tr35-numbers.html) In CLDR patterns the ¤ sign is replaced by the localised currency symbol for the currency being formatted.[[4]](https://www.unicode.org/reports/tr35/tr35-numbers.html) The CLDR specification says that in a standard currency format a negative amount might typically be displayed as something like -$3.27.[[4]](https://www.unicode.org/reports/tr35/tr35-numbers.html) The CLDR specification says locales may also provide an accounting form, in which for en\_US the same amount would appear as ($3.27).[[4]](https://www.unicode.org/reports/tr35/tr35-numbers.html) Financial statements can include negative balances, shown either by a minus sign or by enclosing the balance in parentheses.[[5]](https://en.wikipedia.org/wiki/Negative_number) In bookkeeping, amounts owed are often represented by red numbers or by a number in parentheses, as an alternative notation for negative numbers.[[5]](https://en.wikipedia.org/wiki/Negative_number) ### Use Digit group separators can occur either as part of the data or as a mask through which the data is displayed.[[2]](https://en.wikipedia.org/wiki/Decimal_separator) RFC 4180 says that fields containing commas should be enclosed in double quotes.[[6]](https://www.rfc-editor.org/rfc/rfc4180.txt) The pandas read\_csv function uses a period as its default decimal character and suggests a comma for European data.[[7]](https://pandas.pydata.org/docs/reference/api/pandas.read_csv.html) Before casting, strip the currency symbol, remove the thousands commas and turn surrounding parentheses into a minus sign, keeping the symbol in its own column if it varies. (Meridian's view) Confirm that the file really uses the comma for thousands, since a value like 1,234 means something very different under the comma-decimal convention. (Meridian's view) Python's decimal documentation notes that numbers like 1.1 and 2.2 do not have exact representations in binary floating point.[[8]](https://docs.python.org/3/library/decimal.html) Python's decimal documentation says decimal is preferred in accounting applications which have strict equality invariants.[[8]](https://docs.python.org/3/library/decimal.html) Cast cleaned amounts to a fixed-point decimal type rather than a float, so that totals reconcile to the cent. (Meridian's view) The numerous currencies called dollar use the dollar sign, and the sign is also generally used for the many currencies called peso.[[9]](https://en.wikipedia.org/wiki/Dollar_sign) ## Sources 1. [finetype/labels/definitions\_finance.yaml at main · meridian-online/finetype · GitHub](https://github.com/meridian-online/finetype/blob/main/labels/definitions_finance.yaml) — FineType 2. [Decimal separator - Wikipedia](https://en.wikipedia.org/wiki/Decimal_separator) — secondary source 3. [Currency symbol - Wikipedia](https://en.wikipedia.org/wiki/Currency_symbol) — secondary source 4. [Unicode Locale Data Markup Language (LDML) Part 3: Numbers](https://www.unicode.org/reports/tr35/tr35-numbers.html) — standard 5. [Negative number - Wikipedia](https://en.wikipedia.org/wiki/Negative_number) — secondary source 6. [Common Format and MIME Type for Comma-Separated Values (CSV) Files](https://www.rfc-editor.org/rfc/rfc4180.txt) — standard 7. [pandas.read\_csv — pandas 3.0.6 documentation](https://pandas.pydata.org/docs/reference/api/pandas.read_csv.html) — documentation 8. [decimal — Decimal fixed-point and floating-point arithmetic — Python 3.15.0 documentation](https://docs.python.org/3/library/decimal.html) — documentation 9. [Dollar sign - Wikipedia](https://en.wikipedia.org/wiki/Dollar_sign) — secondary source