We were previously able to view allocated, actual and ETC hours for a resource on each assigned project for all prior months on the Resource Planning - Workloads screen (on both that main screen and the individual resource allocation screen). While looking for information today, we suddenly discovered that all data prior to the current month is now blank.
Why can I no longer see values in prior months on the TSV for this resource?
If the time periods that you are trying to view fall within the available slice range, the next thing to check would be the hire date of the impacted resource. Values will not display on the time scale for dates prior to their hire date. This is expected behavior.
For the out of the box configuration of the available slices used by the time scale views in PPM, see KB000028482.