It really seems to vary, here are 3 screen caps.
16 links on the 1st page, showing 340 new posts.
2nd page has 8 links, says of 332
3rd page has 13 links of 337
The remaining pages showed 16-13 posts it seemed like, I didn't count them all. Sometimes though I'll end up with several pages that are like the 2nd with only 8 or so posts.
My only guess is that the software doesn't accommodate ignored forums very well. Just odd. But no big deal.