Most locales use the Gregorian calendar, but you should consider other calendars when you are creating a localized application. Planning the Globalized PT Application describes the calendars that are used throughout the world. All of the PT application's locales use the Gregorian calendar. Germany and the United States use the Gregorian calendar exclusively; Japan uses the Gregorian calendar and the Imperial calendar (Wareki format) for business purposes. The PT application does not implement the Wareki date format. However, support of the Imperial calendar would make the application more marketable in Japan.