Using a pivot table grouped by months and years would be the most
straightforward.

"Zachary Baker" <Zachary wrote in message
...
I have been given a data set which contains work hours and dates in the
form
of mm/dd/yy. I am trying to sum all the hours worked in each month. A
co-worker suggested I use sumproduct but I'm still not able to achieve the
process. Additionally, the data crosses over years, so I am not quite
sure
how to create a fomula that takes the year into account. Any help would
be
great. Thanks much.

--
Zachary Baker