The New York Times, the WHO pegged extra deaths above the pre-covid norm at about 15 million globally by the end of 2021. This figure, which includes indirect losses from a healthcare crunch caused by a covid crowding-out, is around 9 million above the combined tally reported by governments.
India, with an official covid death toll of roughly 520,000, was estimated to account for at least 4 million deaths. While this broadly conforms with independent studies by other agencies, it has evoked a sharp response from New Delhi, which has sought to poke holes in the methodology that was used for it.
As the controversy draws global attention, the validity of our stance is likely to face scrutiny around the globe. The data in contention is not a head count, but a calculation drawn from national records in conjunction with local surveys and other variables fed into formulae designed to also account for covid-related deaths that were missed.
In the sphere of statistics, this is a standard way to plug information gaps. Based on field data taken from random samples, probabilities can be worked out that offer a fairly accurate big picture.