With numeric values in a gt table, we can perform currency-based formatting. This function supports both automatic formatting with a three-letter or numeric currency code. We can also specify a custom currency that is formatted according to the output context with the currency() helper function. Numeric formatting facilitated through the use of a locale ID. We have fine control over the conversion from numeric values to currency values, where we could take advantage of the following options:

  • the currency: providing a currency code or common currency name will procure the correct currency symbol and number of currency subunits; we could also use the currency() helper function to specify a custom currency

  • currency symbol placement: the currency symbol can be placed before or after the values

  • decimals/subunits: choice of the number of decimal places, and a choice of the decimal symbol, and an option on whether to include or exclude the currency subunits (decimal portion)

  • negative values: choice of a negative sign or parentheses for values less than zero

  • digit grouping separators: options to enable/disable digit separators and provide a choice of separator symbol

  • scaling: we can choose to scale targeted values by a multiplier value

  • large-number suffixing: larger figures (thousands, millions, etc.) can be autoscaled and decorated with the appropriate suffixes

  • pattern: option to use a text pattern for decoration of the formatted currency values

  • locale-based formatting: providing a locale ID will result in currency formatting specific to the chosen locale

We can use the info_currencies() function for a useful reference on all of the possible inputs to the currency argument.

fmt_currency(
  data,
  columns,
  rows = NULL,
  currency = "USD",
  use_subunits = TRUE,
  accounting = FALSE,
  decimals = NULL,
  drop_trailing_dec_mark = TRUE,
  use_seps = TRUE,
  scale_by = 1,
  suffixing = FALSE,
  pattern = "{x}",
  sep_mark = ",",
  dec_mark = ".",
  placement = "left",
  incl_space = FALSE,
  locale = NULL
)

Arguments

data

A table object that is created using the gt() function.

columns

The columns to format. Can either be a series of column names provided in vars(), a vector of column indices, or a helper function focused on selections. The select helper functions are: starts_with(), ends_with(), contains(), matches(), one_of(), and everything().

rows

Optional rows to format. Not providing any value results in all rows in columns being formatted. Can either be a vector of row captions provided c(), a vector of row indices, or a helper function focused on selections. The select helper functions are: starts_with(), ends_with(), contains(), matches(), one_of(), and everything(). We can also use expressions to filter down to the rows we need (e.g., [colname_1] > 100 & [colname_2] < 50).

currency

The currency to use for the numeric value. This input can be supplied as a 3-letter currency code (e.g., "USD" for U.S. Dollars, "EUR" for the Euro currency). Use info_currencies() to get an information table with all of the valid currency codes and examples of each. Alternatively, we can provide a common currency name (e.g., "dollar", "pound", "yen", etc.) to simplify the process. Use info_currencies() with the type == "symbol" option to view an information table with all of the supported currency symbol names along with examples.

We can also use the currency() helper function to specify a custom currency, where the string could vary across output contexts. For example, using currency(html = "&fnof;", default = "f") would give us a suitable glyph for the Dutch guilder in an HTML output table, and it would simply be the letter "f" in all other output contexts). Please note that decimals will default to 2 when using the currency() helper function.

If nothing is provided to currency then "USD" (U.S. dollars) will be used.

use_subunits

An option for whether the subunits portion of a currency value should be displayed. By default, this is TRUE.

accounting

An option to use accounting style for currency values. With FALSE (the default), negative values will be shown with a minus sign. Using accounting = TRUE will put negative values in parentheses.

decimals

An option to specify the exact number of decimal places to use. The default number of decimal places is 2.

drop_trailing_dec_mark

A logical value that determines whether decimal marks should always appear even if there are no decimal digits to display after formatting (e.g, 23 becomes 23.). The default for this is TRUE, which means that trailing decimal marks are not shown.

use_seps

An option to use digit group separators. The type of digit group separator is set by sep_mark and overridden if a locale ID is provided to locale. This setting is TRUE by default.

scale_by

A value to scale the input. The default is 1.0. All numeric values will be multiplied by this value first before undergoing formatting. This value will be ignored if using any of the suffixing options (i.e., where suffixing is not set to FALSE).

suffixing

An option to scale and apply suffixes to larger numbers (e.g., 1924000 can be transformed to 1.92M). This option can accept a logical value, where FALSE (the default) will not perform this transformation and TRUE will apply thousands (K), millions (M), billions (B), and trillions (T) suffixes after automatic value scaling. We can also specify which symbols to use for each of the value ranges by using a character vector of the preferred symbols to replace the defaults (e.g., c("k", "Ml", "Bn", "Tr")).

Including NA values in the vector will ensure that the particular range will either not be included in the transformation (e.g, c(NA, "M", "B", "T") won't modify numbers in the thousands range) or the range will inherit a previous suffix (e.g., with c("K", "M", NA, "T"), all numbers in the range of millions and billions will be in terms of millions).

Any use of suffixing (where it is not set expressly as FALSE) means that any value provided to scale_by will be ignored.

pattern

A formatting pattern that allows for decoration of the formatted value. The value itself is represented by {x} and all other characters are taken to be string literals.

sep_mark

The mark to use as a separator between groups of digits (e.g., using sep_mark = "," with 1000 would result in a formatted value of 1,000).

dec_mark

The character to use as a decimal mark (e.g., using dec_mark = "," with 0.152 would result in a formatted value of 0,152).

placement

The placement of the currency symbol. This can be either be left (the default) or right.

incl_space

An option for whether to include a space between the value and the currency symbol. The default is to not introduce a space character.

locale

An optional locale ID that can be used for formatting the value according the locale's rules. Examples include "en_US" for English (United States) and "fr_FR" for French (France). The use of a valid locale ID will override any values provided in sep_mark and dec_mark. We can use the info_locales() function as a useful reference for all of the locales that are supported.

Value

An object of class gt_tbl.

Details

Targeting of values is done through columns and additionally by rows (if nothing is provided for rows then entire columns are selected). A number of helper functions exist to make targeting more effective. Conditional formatting is possible by providing a conditional expression to the rows argument. See the Arguments section for more information on this.

Figures

Function ID

3-4

See also

Examples

# Use `exibble` to create a gt table; # format the `currency` column to have # currency values in euros (EUR) tab_1 <- exibble %>% gt() %>% fmt_currency( columns = vars(currency), currency = "EUR" ) # Use `exibble` to create a gt table; # Keep only the `num` and `currency`, # columns, then, format those columns # using the "CNY" and "GBP" currencies tab_2 <- exibble %>% dplyr::select(num, currency) %>% gt() %>% fmt_currency( columns = vars(num), currency = "CNY" ) %>% fmt_currency( columns = vars(currency), currency = "GBP" )