Or perhaps it will be on an unspecified day next month, or sometime after 12 October, or even 11 May next year. No one can quite agree, but it is definitely going to happen. India is on the point of becoming only the second member of the billion-people club, 20 years after China achieved the dubious distinction. On its independence, 51 years ago, India's population was 350 million but the population is currently growing at a rate of 15,678,000 people every year, more than any other country.
Dr M Vijayanunni, India's registrar general and census commissioner, harbours few doubts when he insists on 11 May 2000 as the date on which the population will hit one billion. "This date was arrived at on the basis of our census prediction up to 2016," he said.
No matter when it comes, though, it is no cause for celebration. Anjali Nayyar, project director at the Population Council, said: "Population is not just a numbers issue. It is a development issue."
The Indian government pays lip service to birth control. Foreign aid for population control is around pounds 140m annually and the states and central government spend twice that on family planning. But the UN says much of the aid is not taken up because of political indifference, poor distribution and bureaucratic infighting.