SumIF for multiple conditions

I have a series of dates with hours next to them like this:

Week Hours Location
2001.15 1 US
2001.16 4 Brazil
2002.15 7 US
2003.16 3 Mexico

I can do a Sumif and make it add up all the hours in week 2001.15 or I can have it add up all the hour in the US. But how can I make it sum the hours that were in 2001.15 and in the US? Basically I need to do a sumif with multiple conditions. Any ideas? Thanks.

Chuck.

Assuming that Column A does not contain true date values, but contains numerical values, try...

=SUMPRODUCT(--(A2:A5=2001.15),--(C2:C5="US"),B2:B5)

Hope this helps!