New Delhi, Aug 31 (IANS): Work has started on India's 2021 Census and for the first time data will be collected on Other Backward Class (OBC), the government announced on Friday.

The 2021 exercise will use improved technological intervention to ensure that the whole data was finalized within three years, the Union Home Ministry said.

The announcement came after Home Minister Rajnath Singh reviewed the functioning of the office of Registrar General and Census Commissioner here in the presence of Minister of State for Home Kiren Rijiju, Home Secretary Rajiv Gauba and Registrar General of India Sailesh.

"Rajnath Singh discussed the roadmap for undertaking the Census in 2021. It was envisaged to collect data on OBC for the first time. Use of maps, georeferencing at the time of house listing is also under consideration," said a Ministry statement.

It was emphasised that improvements in design and technological interventions be made to ensure that the Census data was finalized within three years after the Census operation, said the statement.

At present, it takes seven to eight years to release the complete data.

A Home Ministry official said nearly 25 lakh enumerators have been trained and engaged for the gigantic exercise.