NEW DELHI // India is now home to 17 per cent - more than one in six - of all people in the world as its population climbed to 1.21 billion in 2011, though growth actually slowed for the first time in 90 years, census officials said on Thursday.
The nation still saw a double digit jump in people, adding 181 million in the past 10 years, said C Chandramouli, the census commissioner. The 17.6 per cent increase was down from 21.5 in the 2001 count.
The last time India showed slowing in population growth was in the 1921 census.
United Nations projections still show that India could overtake China and its 1.34 billion people as the world's most populous nation by 2030, though Mr Chandramouli said a more rigorous analysis of data would be needed before India made its own projections.
The initial numbers show a decline in the number of children under the age of six, down five million since 2001 to 158.8 million. They also indicate a continuing preference for male children over females in a country where female infanticide is still common and the government has banned doctors from revealing the sex of unborn children.
A gender breakdown among children showed fewer girls than boys are being born or surviving, with 914 girls for every 1,000 boys under the age of 6, compared to 927 for every 1,000 in the last census.
"This is a matter of grave concern," Mr Chandramouli said.
Indians continue to favor sons over daughters mostly because of the enormous expenses involved in marrying them. Even the poorest families are often likely to go into debt arranging marriages and paying elaborate dowries to their daughter's new family. Hindu custom also dictates that only sons can light funeral pyres.
"Whatever measures that have been put in over the last 40 years has not had any impact on child sex ratio and therefore that requires a complete review," India's home secretary, GK Pillai, said.
The overall sex-ratio showed a marginal improvement, with 940 women counted for every 1,000 men compared to 933 in the last census.
The numbers released on Thursday were preliminary and official figures and analysis weren't expected to be released until next year.
The census, India's 15th such exercise since 1872, was a mammoth effort spread out over one year. It involved 2.7 million census-takers who surveyed some 300 million households, noting for the first time whether people live in basic huts or concrete structures, have electricity and access to toilets and if they have spent any time in schools.
The questions will help administrators develop policies and set budgets for a nation where 800 million people live in poverty.
Almost all residents, regardless of nationality, are included in the count, even those imprisoned like the Pakistani Ajmal Kasab, who is on death row for his role in the 2008 Mumbai terror attacks. Millions of homeless were also counted.
The census also showed that the literacy rate went up to 74 per cent nationwide for people aged seven and older, from about 65 per cent in the last count.