Is reputation from Area 51 counted towards the commitment score?

According to the updated commitment formula system, the percentage is taken as the minimum of 3 factors:

1. Total Commitment Score / 500
2. Total # of committers / 200
3. Total # of committers with 200+ rep on a single site / 100

I have tried to audit this with Persian Information Technology and Computer, and the numbers I have got are:

1. 268.442750731 / 500 = 53%
2. 162 / 200 = 81%
3. 12 / 100 = 12%

Clearly the limiting factor is #3, the number of "200+ rep commiters". The percentage should be 12%, but it is listed as 8% on the page!

So I wonder where is the missing 4%? It turns out there are exactly 4 users committed to PITC that only has 200+ reps on Area 51. This strongly suggests that Area 51 is not one of the "single sites" in #3. Is it the case? If yes, why is Area 51 excluded?

(The same thing happens for Physics where the percentage should be 87% instead of 82%. But Area-51-only users just account for 3%, I'm still wondering where is the missing 2%.)