There are two India's if you look only from rate of population growth. The four southern states have a similar accrual rates that of the west, and rate of increase in the "northern" states.

To quote the article referenced below:

"..Nine Indian states (Kerala, Tamil Nadu, Andhra Pradesh, Himachal Pradesh, Punjab, West Bengal, Delhi, Karnataka and Maharashtra) had fertility rates less than the replacement level of 2.1.

Kerala and Tamil Nadu, at 1.7, had lower fertility levels than Norway and the Netherlands, at 1.9 and 1.8 respectively."

http://www.indiaspend.com/cover-story/ageing-india-south-ind...