Why doesn't the Allocation Discrepancy portlet show  the same hours as the Weekly Detail, when filtered by the same  Time Scale?

Release: CODFSS99000-15.3-PPM SAAS FedRAMP-Sandbox-Small Environment
Component:

The Allocation Discrepancy portlet uses the last Time Scale period when displaying data.
The weekly detail portlet uses the periods you select in the TSV.

An example is:

We are in week of 8/13
Weekly Detail Allocation 
Prior week (8/6) = 22
Current week (8/13) = 40

Allocation Discrepancy Portlet set for 1 Period and Weekly Time Scale shows
Allocation = 22 (week of 8/6)