But for auctioneers such as Acker Merrall, Bordeaux has become even less important. So far this year, Bordeaux wines have accounted for about 30 percent of sales at his auctions, down from 40 percent in 2013 and 50 percent in 2012, Kapon said.
Acker Merrall, which has been the single largest auctioneer by global sales of fine and rare wines over the last 10 years, has seen sales of wine in most regions outside of Bordeaux grind higher. Even without as much Bordeaux, which tends to be very expensive, Acker Merrall has held its own: The auctioneer earned $32 million in revenue in the six months through June, down slightly from $33.5 million in the same period of 2013.
What's picked up the slack? Kapon said the biggest help has probably been strength in wines from France's Burgundy region. Red and white wine from Burgundy have accounted for 47 percent of Acker Merrall auction sales so far this year. "It's basically replaced Bordeaux," he said.
Strength in Burgundy was obvious at last week's auction. Among the world records set: A single bottle of 2005 Coche Dury Meursault Les Rougeots for $679.25; a magnum bottle of Domaine de la Romanée-Conti La Tache for $9,880; and a single bottle of Henri Jayer Echezeaux for $4,013.75.
One reason Burgundy has held up well is because there's simply less of it to go around. "The key is production size," said Patrick Stella, a collector at last week's auction. "Bordeaux has big production and the prices went crazy. That's not sustainable if demand pulls back," he said. "But Burgundy has guys waiting to get what little they can."
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Indeed, even at a large auction such as Acker Merrall's, it is unusual to see a full case of rare Burgundy. Instead, there were often bundles of three bottles from different cases or even individual bottles. Romanée-Conti may only produce a few hundred cases per year, while some of the most highly regarded Bordeaux chateaux produce several thousand per year.
Wine collectors say that Bordeaux producers may have tried to control supply as the market ran up a few years ago to drives prices even higher. But that may have prompted collectors to look elsewhere as prices reached stratospheric levels. "If the [Bordeaux] producers aren't careful they'll lose a generation of wine drinkers," Kapon said.
Still, many older Bordeaux wines remain rare enough that prices have held up fine. The 1982 vintage of Mouton Rothschild, for instance, sold well above the minimum estimated price of about $1,000 a bottle in several lots at last week's auction. "The older ones are better investments because they are scarcer," Kapon said. "People are also going for these older wines because you can drink them right now."