How to get expression to sum by field not total

[mgoddard]

I have a  pivot table pulling data from multiple tables and not displaying what I would assume to be the correct summation of the data.  Each FC Month (period) in this example had a salesQTY in each SIOP period, however the total for all three SIOP periods is being displayed in each row. 

For Example 2401 should be:

P1 = 336,000

P2 = 163,500

P3= 163,500

[Chanty4u]

try this

Aggr(Sum(SalesQTY), FC_Month, SIOP_Period)