I'd start on Debra Dalgleish site:
http://www.contextures.com/xlFunctions03.html (for =index(match()))
and
http://contextures.com/xlFunctions02.html#Trouble

On 05/14/2010 09:56, Curly wrote:
I have three columns to the left column K each has a header with the year
number. 2008, 2009 and 2010. Underneath each of the three columns I have
numerical data. On the same header row I have a drop down list in K1. So
when I pick 2009, I want the calculations in K2, K3 downward to use the
corresponding data in column that has the matching year.

2008 2009 2010 2009 (drop down)
2 3 6 3*10

If I choose the drop down of 2008 then the formula should be 2*10
If I choose the drop down of 2010 then the formula should be 6*10

The actual formula is much more complicated involving INDEX/MATCH, but I
think this should relay the idea.

Thanks for any help.