This module provides numeric data types for PostgreSQL that use numerals (words instead of digits) for input and output.

* numeral: English numerals (one, two, three, four, ...),
short scale (10^9 = trillion)
* zahl: German numerals (eins, zwei, drei, vier, ...),
long scale (10^9 = Milliarde)
* roman: Roman numerals (I, II, III, IV, ...)