Ghost,
I don't have a direct answer, but perhaps the figures below might help you (the All Forms Data only started in FY2011, so there are no comparable figures for FY2010)
The figures are the cumulative EB I-485 receipts through the year i.e. Q2 figure also includes Q1 etc. The figures are for all Countries, including IC.
----- FY2011 -- FY2012 -- Difference
Q1 -- 19,656 --- 35,445 ---- 15,789
Q2 -- 36,492 --- 95,139 ---- 58,647
Q3 -- 56,163 -- 124,027 ---- 67,864
Q4 -- 78,302 -- ???????
I would be slightly worried if EB2-IC did not account for somewhere around 60k.
There will have been some increase in EB5. I don't think EB3 accounts for many as there are unlikely to be many PWMB for any of the EB3 Cut Off Dates. In any case, Year-On-Year the numbers should be comparable.
If EB4 is reasonably constant, and if the increase is not due to EB2-IC, then it would have to be for either EB1 or EB2-WW, both of which would not be good for SOFAD in FY2013. Since EB4 was low last year, possibly there may have been an increase this year - I have no idea.
Generally, the increase is consistent with how EB2-IC Cut Off Dates moved through the year.
The Q4 figures may be quite interesting. With EB2 essentially absent and EB3 not accounting for many, the figures may give some insight into the EB1 numbers, if we can net off EB4 and EB5 and make an estimate for EB3.
Edited to add:
I did a very quick and dirty analysis and came up with a figure of approaching 30k for EB2-WW for FY2011. That in turn would give about 61k for EB2-IC in FY2012 if EB2-WW were prorated accordingly. Bear in mind that is a very quick analysis and subject to a fair variance because of the number of assumptions used.