   YEAR[(2|4)]

A year in two-digit or four-digit format. The default is four-digit format.
In four-digit format, the
allowable values are 1901 to 2155, and 0000.
In two-digit format, the allowable values are
70 to 69, representing years from
1970 to 2069.  MySQL displays YEAR values in
YYYY format, but allows you to assign values to YEAR columns
using either strings or numbers. The YEAR type is unavailable prior
to MySQL 3.22.
