We recently upgraded our instances from 7.5 -> 9.11 (with an intermediate step to upgrade to 8.0).
In our custom portlets with currency columns (bar charts, list charts, etc) the currency columns no longer display the proper format. The datasource columns are currency and USD is our base currency. I don't see any reason why they no longer show properly.
For example, where the dollar amount used to show "$1,000,000" it now shows as "1E6".
When you upgrade PPM to 9.11, Oracle version must have upgrade. Beacuse of that I think your db team reinstall new oracle version. Maybe a parameter unnoticed which is define number format or currency format.
IT Governance Professional & PPM Solution Architect