[Mark McLeod]

Here's a late addition of when each event reached initial capacity (blue bar) and when it finished drawing from the waitlist if it reached max advertised capacity (red bar). Those events where the blue/red bar reaches the top are those that never reached maximum capacity. The scale is in days from registration opening. The blue bar can be thought of as the free market, while the red bar represents the controlled market of the Regional Director/FIRST HQ's discretion. The Blue goes quickly, but the red lags.

The first chart is in order from left to right based on which events reached initial capacity first.
The second chart is in order by when the team list was finalized from the waitlist.

FIRST HQ is highly concerned with all teams getting their first Regional, but don't care so much if they get a second Regional, so some waitlists drag on and never seem to close.