Total Not Summing Correctly on Calculated Fields in Pivot Table
 

I have a spreadsheet showing Total Sales for Rep and Quarterly Quota.
I am also calculating number of weeks remaining in each quarter. When
remaining weeks = 1 I set the value to 1. In the Pivot Table I'm
showing what the Quarterly Quota is and the Total Sales per Quarter.
Then I have two calculated fields:

Difference (Quota - Total Sales) per quarter

Sales Per Week (Difference / Weeks-Left) This is sales needed per week
to meet quota

Everything works great except Total Sum of Sales Per Week not summing
correctly.
Should be $810 + 180.60 = $991.55.
I am assuming I can create a calculated field from another calculated
field but maybe that's my problem.


SREADSHEET:
Total
Date Rep Item Sales Quota Weeks-Left
-----------------------------------------------------------------------------------------------------------------------------------
1/1/2005 Jones $1,000.00 1
4/1/2005 Jones $1,200.00 2
7/1/2005 Jones $1,400.00 0
10/1/2005 Jones $1,600.00 0
1/6/2005 Jones Pencil $189.05
4/1/2005 Jones Binder $299.40
6/8/2005 Jones Binder $539.40
8/15/2005 Jones Pencil $174.65
9/18/2005 Jones Pen Set $255.84
10/2/2005 Jones Pen $575.36
2/18/2006 Jones Binder $19.96
7/4/2006 Jones Pen Set $309.38

PIVOT TABLE:

Rep
Years Date Data Jones Grand Total
---------------------------------------------------------------------------------------------------------------------------------
2006 Qtr1 Sum of Quota $1,000.00 $1,000.00
Sum of Total Sales $189.05 $189.05
Sum of Difference $810.95 $810.95
Sum of Sales Per Week $810.95 $810.95
----------------------------------------------------------------------------------------------------------------------------------
Qtr2 Sum of Quota $1,200.00 $1,200.00
Sum of Total Sales $838.80 $838.80
Sum of Difference $361.20 $361.20
Sum of Sales Per Week $180.60 $180.60
-----------------------------------------------------------------------------------------------------------------------------------
Total Sum of Quota $2,200.00 $2,200.00
Total Sum of Total Sales $1,027.85 $1,027.85
Total Sum of Difference $1,172.15 $1,172.15
Total Sum of Sales Per Week $390.72 $390.72

Any ideas?