Per CA Clarity Project and Portfolio Manager Change Impact and Upgrade Guide for Clarity 12.1 Service Pack 1 - In the Studio Section or Chapter 2, a new hidden filter field has been provided to allow filtering on Resource's active status.
Here is how you can configure a similar field for investment to show on the filter section for the Resource Planning page: Allocation tab: Weekly Detail portlet.
1. Administration > Portlets > filter for "Weekly Detail"
If you go to List Filter Section > Layout, you will not find the "Investment Active" field
2. Go to Fields, change "Display" drop down from "Selected" to "All"
3. Look for the field "Investment Active", when found click on the Properties icon
4. Uncheck "Hidden in Filter" check box
5. Save and Return
Back on the portlet on the Home side, once you have clicked on the expand icon on the portlet (on 13.x this icon is placed on the far left right before the portlet name), you will now see the Investment Active filter field, and can set the value to either Yes or No to help narrow down the data returned on the portlet.
You can take the same step to show the hidden "Active Resource" filter on the Workload portlet mentioned in the Change Impact and Upgrade guide.
Reference TEC561174 for further information on how inactive status affects the Resource Workload portlet.