If you right-click a task and go to “View Task Reports” , the Job Reports pane that is displayed does not have the filter set up properly. If you go to the “Edit Filter” settings for the newly-created Job Reports pane, everything appears to be set up correctly, but the match type hasn’t actually been changed (as if the signal from the match type combo box hasn’t fired).
The consequence of this is that, if you right-click task 1 and view its reports, you’ll see the reports for tasks 1, 10-19, 21, 31, 41, …, 100-199, and so on. The pane that appears actually has its filter set to (Task ID, Contains, 1) under the hood, but the condition combo box will still say Equals. If you change the condition to anything else and then back to Equals and then click OK, the proper filter will be applied.
This is in 7.0.2.3