Completely agree on this one! I'm used to with other EPM systems being able to show trending reports e.g. on status. It's very manual to produce such reporting when as you say the only archives you have of this information is in PDFs that have been taken each reporting period.
Another way to ask for this functionality would be to add the ability to run the report with "as of" dates. For example, run the report is if it was a specific date, not just the current date.