The Olympic Games are still three months away. But the big international auction houses are already shrieking about new world records this week, with all the frenzied excitement of top-class athletes. An evening contemporary art sale at Sotheby’s in New York generated a new top price – $45m – for a Roy Lichtenstein oil painting. Twenty-four hours earlier, arch-rival Christie’s secured an even juicier $87m for Mark Rothko’s Orange, Red, Yellow. Proceeds of $388m from the latter’s evening auction were trumpeted as the best-ever result for a sale of postwar and contemporary art. Following the $120m paid for Edvard Munch’s 1895 version of The Scream, demand for modern artworks appears to be in rude health.

But the underlying picture may be more complex. According to Art Market Research, the top end of the contemporary art market soared between 2000 and 2008, halved over the next 12 months and then rallied very strongly in 2011. A new coterie of wealthy buyers from Asia, Russia and the Middle East is said to be one of the main drivers. To some extent, price gains at the top end have filtered down; differentials are carefully calculated. Nevertheless, the lower end of the contemporary art market has remained much more sedate.

In spite of the headline-grabbing results achieved last week, not everything sold: at Sotheby’s, for example, the sale rate was 81 per cent. Art market tracker Beautiful Asset Advisors also reckons that sold lots in the two auctions for which there were prior purchase price data generated an average compound annual return of just over 6 per cent (with an average 14-year holding period). That still beats the total return on the S&P 500 index, but is less stellar than earlier results. Perhaps there always comes a time when even prestige artworks run out of puff.