sum values for a financial year

Hi all,

I have a set of about 60 month-end dates (60 months, 5 years), not necessarily starting at the beginning of a financial year (1 apr to 31 mar)....say from A1 to A60... I would like to sum all values in the array range B1 to B60...for the same financial year...such that each cell below a particular date (in row C) should show the sum of values in the financial year it falls in.

Pls help if you have any ideas.

Thanks,
Abhishek