Hi

I would have a second Values column in my source table.
Presumably, you have some way of identifying purchase rows from income rows.
Let's assume that column C contains a an I for Income or P for Purchase.
Let's also assume the existing Value column is column F
so in the new Values column (Value2)
=IF(C2="P",F2*-1,F2)
Copy down

Extend your PT source to contain this new Value2 column, and drag that to
the data area in place of the existing Value column.
--
Regards
Roger Govier

"DRW" wrote in message
...
In Excel 2007, I use pivot tables to analyse income and expenditure.

I would like to be able to deduct the expenditure from the income, but
Excel
seems to only provide an addition for Grand Totals, not the ability to
deduct.

Any suggestions gratefully received.

Many thanks.