Christians, Sikhs, Buddhists and Jains together make up the remaining 6% of the population.Based on data available in India's decennial census and the National Family Health Survey (NFHS), the Pew study examines how the country's religious composition has changed, and the main reasons behind the changes. India's population has more than trebled following the 1947 division of a colonial state into Hindu-majority India and Muslim-majority Pakistan - from 361 million people in 1951, to more than 1.2 billion people in 2011. (Independent India held its first census in 1951, and the last one was conducted in 2011.)
During this period, every major religion in India saw its numbers rise, the study found.