Use these year tokens if you wish to display the year only at the beginning of the year, only at the end or only in the first and last months.
•[YYyy] will only appear in January.
•[yyYY] will only appear in December.
•[YYYY] will only appear in January and in December.
Some remarks :
•Do not confuse the [yyyy] and [YYYY] tokens; they are very different.
•Use filler tokens suffixes if the current token is next to a separator such as "-" or "/" and you do not want that separator to appear when the conversion of [YYYY] is blank.
Use the comparative year token, if you need more options over the condition under which the year number appears than available with this token.