YEAR
Returns the year as a number according to the internal calculation rules.
This function is part of the Open Document Format for Office Applications (OpenDocument) standard Version 1.2. (ISO/IEC 26300:2-2015)
YEAR(Number)
Number shows the internal date value for which the year is to be returned.
=YEAR(1) returns 1899
=YEAR(2) returns 1900
=YEAR(33333.33) returns 1991
=YEAR(DATEVALUE("2010-09-28")) returns 2010.
