1. Sir, I think, earlier to January, 2016 the rate of increase in DA was being calculated based on recommendations of 6th Pay Commission which was effective w.e.f. January, 2006. Now, the Government has merged such increase in DA upto January, 2016 ( approx. 125%) with the basic pay. Hence now there is less %age of Dearness Allowance as declared by the Govt.
2. Further, I understand that the increase in DA is based on the increase in prices as observed by the appropriate Govt. during a specific period. It is accordingly less or more depending upon increase of prices during such specific period as reported by concerned agencies.