With a collective wealth of $170 billion, the 40 richest business people accounted for over 22 per cent of India’s GDP, which stood at $775 billion (in 2005-06). The top ten richest alone were worth $112 billion. The ranking includes 36 billionaires, nine more than last year, with the bull run in the stock market playing a key role in inflating the fortunes of the business tycoons, besides the booming real estate market.

The minimum net worth needed to make the cut rose to $790 million up from $590 million previously, Forbes said. But the list’s biggest loser was Anurag Dikshit, who slipped from 10th to 29th rank, on the back of a slide in the stock of his Internet gaming outfit — PartyGaming — over regulatory issues.

Many of the billionaires who feature in the list have been hogging the media limelight for negotiating major deals, including Videocon Industries CMD Venugopal Dhoot for engineering the Daewoo Electronics deal and Kumar Mangalam Birla for acquiring rival Tata’s stake in telecom joint venture Idea.

For people with fortunes in publicly traded companies, net worths were calculated using November 6 market prices and exchange rates. Privately held companies were valued by coupling estimates of revenues or profits to prevailing ratios for similar publicly traded companies.