Review Dashboard shows inconsistent thinking
In the Review Dashboard, if you select Reviewer Progress, the Data Option says All items but the results count is by Document. If, on the other hand, you choose to report on Tag Status, the result count is by item. All charts and tables in the dashboard should be configurable so that the user can select counts by item or document. At the moment totals cannot be sensibly compared to measure perforance or progress.
On another point, the Tag Status chart has a column heading of Items. If you export this to a CSV file, the column heading says Documents!