How to use chart column names in an expression

[#1]

Any suggestions on how to use chart column names in an expression instead of using column numbers. For example if my expression currently reads:

column (1) + column (2)

.... And in my pivot column 1 is titled "2006 Sales" and column 2 is "2007 Sales"

How can I use the column names in my expression?

I have tried the following:

column (2006 Sales) + column (2007 Sales)

column ([2006 Sales]) + column ([2007 Sales])

But it does not work. Any ideas? Thanks.

[#2 · Accepted solution]

=[2006 Sales]+[2007 Sales]

[#3]

Thanks! That worked.