The data will be misused and polarize the Indian polity. However, fine print should be checked before the politicians raise the temperature.

And what is this hot stuff? Muslims are the fastest growing group in India and Hindus have dropped below 80 percent of the population for the first time since independence, shows 2011 census data on religion. It was released on Tuesday by the Registrar General and Census Commissioner.

The data shows that while the general population grew at the rate of 17.7% between 2001 and 2011, the growth rate was 16.8% for Hindus, 24.6% for Muslims, 15.5% for Christians, 8.4% for Sikhs, 6.1% for Buddhists, and 5.4% for Jains.

However, between 1991 and 2001, the Muslim population grew 29.3% but between 2001 and 2011 the growth was 24.6%, indicating slowing of their numbers.

Still, the numbers could revive a divisive debate on religion as it reveals that the proportion of Hindus, Sikhs and Buddhists in the total population shrank in the decade to 2011. There has been negligible change for Christians and Jains.

The data has been released ahead of the Bihar assembly polls that are likely to have far-reaching impact in the state. The proportion of Hindus in the state has seen a marginal decrease from 83.23% in 2001 to 82.69% in 2011, whereas that of Muslims has seen a marginal increase from 16.53% to 16.87% in 2011.

The bland press note of the ministry of home affairs (MHA) said “the proportion of Hindu population to total population in 2011 has declined by 0.7 percentage points (PP); the proportion of Sikh population has declined by 0.2 PP and the Buddhist population has declined by 0.1 PP during the decade 2001-2011. The proportion of Muslim population to total population has increased by 0.8 PP. There has been no significant change in the proportion of Christians and Jains.”

The census data, which was compiled in 2011, says India is home to 966.3 million Hindus, who make up 79.8% of the population. There are 172.2 million Muslims (14.2% of the population); 27.8 million Christians (2.3%) and 20.8 million Sikhs (1.7%). The data also shows there are 8.4 million Buddhists with a 0.7% share of the population and 4.5 million Jains, making up 0.4% of the population.

Some key states where the proportion of Muslims increased during the decade are: Assam which saw an increase from 30.92% in 2001 to 34.22% in 2011, West Bengal (from 25.25% in 2001 to 27.01% in 2011) and Kerala (24.70% in 2001 to 26.56% in 2011).

In politically crucial state of Uttar Pradesh, the proportion of Hindus fell from 80.61% of the population in 2001 to 79.73% in 2011, whereas the proportion of Muslims increased from 18.50% in 2001 to 19.26% in 2011.

The rise of Muslim population is in fact a global phenomenon. According to The Future of World Religions: Population Growth Projections - a study by Pew Research Center, between 2010 and 2050, the population of Muslims is expected to increase 73%, to 2.8 billion, resulting in an increase in their proportion in world population from 23.2% to 29.7%.