India, June 5 -- India will finally start its new census from March 2027, the ministry of home affairs announced on June 4. The announcement puts the reference date at March 1, 2027, except for high-altitude hilly areas where the reference date is October 1, 2026. To be sure, one has to wait for the detailed gazette notification to ascertain whether these reference dates are for population enumeration or house-listing. The latter has traditionally preceded the former by a few months in the conduct of the census in India. The census is being conducted with a delay of six years. While the government has always maintained, including in the latest press release, that the delay was on account of the Covid-19 pandemic, the claim does not pass muster. India has conducted many statistical and mass exercises, including multiple surveys and elections since the pandemic, and some are not very different in scope from the census. While the reasons for the delay - it could have been the dilemma on whether to enumerate caste or not - are best known to the government, what is important is that we will finally have a census. The census data is not just a headcount of the population. It is pretty much the lodestar for building many other databases in India. All of them have become obsolete because of the delayed census. To be sure, it is important to sound a note of caution even as we welcome the announcement of a census date. One can flag at least two key concerns. The census will enumerate caste in the entire country for the first time after 1931. This is easier said than done given the vast heterogeneity in India's social landscape and the political sensitivities while matching them with constitutionally mandated social categories for affirmative actions. It is important that the design for this enumeration is done transparently to avoid post-facto controversies. A similar consultative and transparent approach should be followed for other data collection heads as well. India has changed drastically since 2011 when the last census was carried out. Given the fact that the census will be conducted on hand-held electronic devices - most government surveys are now conducted this way - the collection and publication of the data should not take as much time as its previous versions. A detailed timeline of data releases, beginning with the provisional numbers, should also be announced forthwith. Transparency on both these counts will reduce controversies and facilitate this critical exercise....