Veni,
I am basing the figures on the real life conversion ratio seen in Jan-July 2007. I think that is fair for the remainder of 2007, but I don't use it beyond then.
Although the PERM figures show a 4 to 1 ratio, there seem to be different conversion rates to I-485 for China and India.
We know the reality in the USCIS Inventory and Demand Data for 2007 to date is that the ratio of I-485 cases is nearer 2 to 1 for India to China.
I have taken that into account, as well as the actual monthly totals individually for China and India in the period August to December 2007.
If I use exactly the same figures in August to December 2007 as Jan to July 2007, the India number rises to 9.1k, if that helps you.
Possibly my China figures might be slightly high and India's slightly low post July 2007, but I don't think by huge margins.