Change years in column to one year

I have a column of formated dates and need to change them all to the same year. i hope this is not too trivial a question.
thanks chris

You could use a helper column, e.g. if your dates are in column A and you want to change them all to 2008 dates then put 2008 in C1 and use this formula in B1 copied down

=DATE(C$1,MONTH(A1),DAY(A1))

Note: if any of your your dates are 29th Feb and the year in C1 is not a leap year then that date will become 1st March in the relevant year.