At what time and how often are the figures http://area51.stackexchange.com/proposals/43502?phase=beta updated?
I do not know when the page is updated but it is plain that some of the information currently displayed is nonsense.
Consider the following.
Every site needs a solid group of core users to assist in moderating the site. We recommend:
150 users with 200+ rep (on pace for 66 users at 90 days)
10 users with 2,000+ rep (on pace for 6 users at 90 days)
5 users with 3,000+ rep (on pace for 2 users at 90 days)
Apparently the projection uses the time-honored method (If 3 men dig a ditch in 7 days ...) to decide that, since after 40 days there is one user with 3k rep, in 50 days time there will be one more! I would be VERY surprised if the target of 5 users with 3K rep was not met well within 90 days.
On the other hand, the projection of 66 users with rep between 200 and 2000 may even be too optimistic.