You'll actually need to do this in either two reports, or a report with a sub report.
All ID's in Table 2
Just include Table 2. In the report header or report footer, create a summary that is the distinct count of the ID field.
All ID's in Table 3 that aren't in Table 2
- Add Tables 2 and 3.
- Link from Table 3 to Table 2.
- Right-click on the link, and select "link properties". Change the link to a "Left Outer Join".
- Set a Record Selection filter that looks like this (you'll have to edit the selection formula to do this):
IsNull({Table2.ID_Field})
- Create a summary to do a distinct count of the id field in Table 3.
-Dell