Bangladesh contains the second largest (after Indonesia) Muslim population in the world. In 1981, 86.6 percent of the population was Muslim. The proportion of Muslims increased from 85.4 percent in 1974 to 86.6 percent in 1981. On the other hand, the proportion of Hindu population dropped from 13.5 percent in 1974 to 12.1 percent in 1981.
The increase in proportion of Muslim population may be attributed to higher birth rate among the Muslims. Census records from 1872 to 1981 clearly indicate that birth rate among the Muslims was always higher than that of the Hindus. The Buddhists constituted about 0.6 percent of the population in both 1974 and 1981 censuses. There are about 175,000 Christians in Bangladesh. The percentage of Christians was about 0.3 percent.