Repository view not showing all revisions

Hi!

In my Changes->Repostory view, I am seeing a subset of the revisions.

Weirdly, the revisions go back in time to 2007 but only a small sampling are shown (sometimes one or two per month, though there were tens or hundreds).

If I increase the "Changelists to cache initially" option, I get more revisions filling in the gaps.

What's going on? How can I see a contiguous block of revisions, or, even better, all of my revisions?

Thanks,

Dave