Can someone advise if it is possible change something in Excel 2007.

Whenever I pivot any data the values fields ALWAYS comes up as count instead
of SUM. 99 times out of a 100 I need it to be SUM. I'm currently having to
go into each set of data and change to SUM each time. Anyone know if there
is a way to get it to automatically come up as SUM?

Or is the issue with the data not the pivot functions, however the data does
SUM when manually changed.

Many thanks in advance for any help provided

Tom