Every now and then, somebody comes up with a new figure for the number of people coming into Bombay every day. The figure of 300 families -- about 1500 people -- has been bandied about for years. Last year, Newsweek called it 400 families -- about 2000 people.
Last month, I sat in a dark Delhi auditorium and listened to Vijaypat Singhania, the industrialist and celebrated hot-air ballooner, raise the stakes. Bombay must cope, he said up there on the stage, with a "net migration" of 8000 -- eight thousand -- people a day. Later in his presentation, he repeated this.
Where did Mr Singhania come up with that number from?
More important, why didn't he do some simple arithmetic? 8000 people a day multiplied by 365 days in a year: that's about 3 million people a year coming into Bombay. Is it even conceivable that a city of something like 15 million is increasing its numbers by 20 per cent a year, and that without accounting for "natural" growth, meaning babies?
So what's the truth? As I wrote here, migration into Bombay has been falling -- both in absolute numbers and as a percentage of the city's growth -- for years. It is now likely less than -- ready? -- 200 people a day. Natural growth, meaning babies, is three times heavier a contributor to Bombay's growth than inward migration.
Yet migration and births together add up to a tenth of Mr Singhania's 8000. So I still wonder where that figure came from. Ideas?