I'm trying to create a pivot chart based on purely periodic data stored
in an external database.

The period name is on the X axis. I have periodic costs and revenues,
with which I calculate the periodic metric Multipler. I want to chart
year-to-date Multiplier on the same pivot chart.

Using "Running Total" field settings I can derive YTD costs and
revenues, but I can't for the life of me figure out how to build a YTD
Multiplier within the pivot table so that I can get the YTD Multiplier
on the same pivot chart.

Obviously I can calculate the YTD Multiplier outside of the table and
do a regular chart, but I'd prefer to stick to a pivot chart. Am I
spinning my wheels?

Oh, using XL 2003, FWIW.