Should sumproduct formula be used?

[alltheway]

A month is to be selected upfront in my worksheet.
Say, it is now Feb2011. Hence, dropdown 2 is to be selected.

I have Actual profit numbers reflected for Jan2011-Dec2011 and Budget profit numbers reflected for Jan2011-Dec2011.

If Period 2 is selected, I need a cell to be able to add Jan2011 Actual + Feb2011 Actual + Mar2011 till Dec2011 Budget numbers.

What should the formula be?

I have attached a sample worksheet for this query.

Hope someone can help me...........................

[Huron]

You could use

=SUM(A8:INDEX(A8:L8,MATCH(B3,A4:L4)))+SUM(INDEX(M8:X8,MATCH(B3,M4:X4)+1):X8)