This analysis builds on those carried out by Drew Streib and Jason Harris. They show the state of the Web-of-Trust at regular points of time. Footsie takes their data and shows how the Web of Trust changes over time.
The first graph attempts to describe how big the Web of Trust is. It does this by graphing the size of the reachable set and the strong set. Note that the reachable set is a superset of the strong set.
The second graph attempts to describe how well-connected the Web of Trust is. It estimates this in a similar way to how stock markets attempt to show how the market is performing. At each sample point, we take the average MSD of the top 50 and top 1000 keys. This graph also shows the top key, the 50th key and the 1000th key to track these psychologically significant positions. These lines all move in approximately the same way, so we can be reasonably sure that this is a good estimate.
Some of the events that have had a big effect on the graph include:
In case you want to reproduce these results yourself, here's the code (signature). Please don't laugh at my Perl abilities.