With 1,210,193,422 residents reported in the 2011 provisional census report, India is the world's second-most populous country. Its population grew by 17.64% from 2001 to 2011, compared to 21.54% growth in the previous decade (1991–2001). The human sex ratio, according to the 2011 census, is 940 females per 1,000 males. The median age was 28.7 as of 2020. The first post-colonial census, conducted in 1951, counted 361 million people.[354] Medical advances made in the last 50 years as well as increased agricultural productivity brought about by the "Green Revolution" have caused India's population to grow rapidly.
The average life expectancy in India is at 70 years—71.5 years for women, 68.7 years for men. There are around 93 physicians per 100,000 people.[356] Migration from rural to urban areas has been an important dynamic in India's recent history. The number of people living in urban areas grew by 31.2% between 1991 and 2001. Yet, in 2001, over 70% still lived in rural areas. The level of urbanisation increased further from 27.81% in the 2001 Census to 31.16% in the 2011 Census. The slowing down of the overall population growth rate was due to the sharp decline in the growth rate in rural areas since 1991.[360] According to the 2011 census, there are 53 million-plus urban agglomerations in India; among them Mumbai, Delhi, Kolkata, Chennai, Bangalore, Hyderabad and Ahmedabad, in decreasing order by population.[361] The literacy rate in 2011 was 74.04%: 65.46% among females and 82.14% among males. The rural-urban literacy gap, which was 21.2 percentage points in 2001, dropped to 16.1 percentage points in 2011. The improvement in the rural literacy rate is twice that of urban areas.[360] Kerala is the most literate state with 93.91% literacy; while Bihar the least with 63.82%.