Navreet Kang, secretary, Department of Empowerment of Persons with Disabilities, said as per the 2011 census, 2.68 crore people are there with disabilities, but the certificates issued by various states are more than that number.
"As per the 2011 census, the figure (people with disabilities) is 2.68 crore. It comes to about 2.23 per cent of the population (of India). That figure is probably an underestimation." he said.
"The WHO estimates that worldwide the number of people with disabilities is 10 to 15 per cent (of the total world population)," he said.
"The victims of acid attack were also included in the Rights of Persons with Disabilities Bill-2016," he said.
In the new Act, many more disabilities have been included in its definition. So as it is, it will go up in the next census, he said.
"I would admit that it (the 2011 census figure) is probably an underestimation and it is shown by the fact that the number of disability certificates issued (by various states) is more than the people shown in the census of that state," he said.
"The states also say that your (2011) census figures are wrong," Kang said on the sidelines of a programme organised by Microsoft.
He said the earlier definition of disability was largely confined to physical and locomotive disabilities. The new Bill which was passed in December 2016 has included 21 more disabilities in the list.
Some specific problems, like acid attack victims, were included on the suggestion of the Supreme Court," he said.
According to him, the Centre has taken up funding of over 1,700 government buildings in various states to be refurbished and enabling them to be accessible to all.
He said the 'Accessible India' campaign, which was launched in 2015, has a three-pronged strategy.
According to the campaign, all the new buildings must be accessible to all.
Secondly the transportation system, including road, air and rail, should have facilities such as lifts, ramps, toilets and parking places for people with disabilities.
The third strategy would be to provide necessary provisions in information and communication technology devices, he said.