Hi,
This article from MS shows how to calculate if a given year is a leap year:
If you are always entering entire fiscal years, then you just need to use this formula to reference the year of the end date. Supposing your start date, 1st July 2011, is in cell A1, and your end date, 30th June 2012 is in cell A2, you would change the formula as follows:
Code:
=IF(OR(MOD(YEAR(A2),400)=0,AND(MOD(YEAR(A2),4)=0,MOD(YEAR(A2),100)<>0)),"Leap Year", "")
If you want to be able to enter any set of dates, which may or may not span multiple years, then it is possible but the formula will become considerably more complicated.