The Economic Survey 2015-16 has a whole chapter devoted to tax/GDP! Building on a recent special column with Praveen, my latest Mint piece dissects the ES's claim that India isn't an outlier, and points to 1991 as a year of a structural break.

http://www.livemint.com/Opinion/vjSlh6i79zBZHlJtZ4vVsO/Tax-to-GDP-ratio-redux.html