Date determination and sums
 

I need a bit of help with this one. I have the following worksheet setup:

Column A - Date
Column B - Ticket #
Column C - Task # (within ticket #)
Column D - Total hours billed

I am attempting to calculate (onto a new worksheet) the total number of
hours billed for each month (based off of a validation from column A).
Basically, on another worksheet I have each month broken down into seperate
rows (it's about 20 - so almost 2 years worth of data). Is there a way to
total column B (per month) and sum up how many tickets there were in a month
or how many hours were billed based on a given month?


Thanks in advance for any help,
UCG