IN this troubled economy, Christie’s and Sotheby’s are doing a booming business. Christie’s year-end results were £3.6bn, up nine per cent. The percentage rise in sales of contemporary art was even better, at 22 per cent. Sotheby’s doesn’t announce its complete results until the end of February, but its total auction sales increased by 14.5 per cent with contemporary art up a significant 34 per cent.

The gravity-defying surge of this segment of the art world is surprising, but only at first glance. The bulk of revenues comes from ‘ultra-high net worth’ individuals, many of whom operate at a level far above national economies.

Even those who have taken blows in recent years remain super rich. If they were worth £3bn in 2007, maybe they’re worth £2bn now. It’s not like they’re feeling the pinch. The burden for the stinking rich is what to do with their money. There is currently no interest to be earned on cash, so they can’t leave it in the bank. The property market is nearly paralysed and, for these globetrotters, the drawback of real estate is that it is tied to specific currencies.

Fifteen years ago, financial advisers were not in the practice of recommending that rich people diversify their portfolios by buying art. Now, it is the norm. While buying emergent art is high-risk, speculative investment, acquiring established masterpieces is perceived as the opposite — a back-up in hard times. If all goes wrong in the world, if the eurozone cracks, the Middle East erupts in war, and a tsunami hits Manhattan, that rare, portable 1964 Marilyn by Andy Warhol will still be worth something.

The auction houses are fostering a globalisation of taste with the help of galleries with international outposts such as Gagosian, Hauser & Wirth and now White Cube. While wealthy Belgians used to spend their money differently from wealthy Indonesians, this is decreasingly the case.

During the contemporary sales that will take place in London on Feb 14 and 15, bidders from four continents are likely to converge on many lots, including a classic red squeegee-blurred abstract painting by Gerhard Richter (estimated at £2.5m-£3.5m at Sotheby’s) and a black and white canvas by Christopher Wool emblazoned with the giant word ‘FOOL’ (expected to fetch £2.9m-£3.9m at Christie’s).

A decade ago, few would have predicted that the most insatiable buyer of record-priced contemporary art would be the Qatari royal family (who are sponsoring the forthcoming Damien Hirst retrospective at Tate Modern). In 2007 they bought Hirst’s Lullaby Spring pill cabinet for almost £9.65m, then the highest price ever paid for a work by a living artist.

It is worth noting that Sotheby’s and Christie’s 10 highest-spending families may be responsible for as much as 10 per cent of their revenue. This teeny elite includes the Qataris and, most likely, Russian oligarchs, US hedge-fund managers, Chinese billionaires, and Europeans with relatively ‘old money’. These people use Christie’s and Sotheby’s as an upmarket department store. If these players drop out of the market, the auction houses’ figures wouldn’t look so hot. As they say in the business, the market is ‘thin’ at the top. — The Guardian, London