A CalendarPeriod represents the abstract concept of a time
period that has a canonical start. Grammatically, "the start of the
current CalendarPeriod". All calendar times begin at 12 AM US
and Canadian Pacific Time (UTC-8).
A month. Month starts on the first day of
each month, such as January 1, February 1, March
1, and so on.
A quarter. Quarters start on dates January 1,
April 1, July 1, and October 1 of each year.
A year. Year starts on January 1.