All those real-estate surveys that kept reporting ever-increasing prices despite stories of an ailing housing market? History. According to numbers released today by four brokerage firms and the website Streeteasy.com, Manhattan has officially contracted the same illness that has felled housing markets across the country.

Many of the usual measures — average prices, median prices, transactions — are way down. Per the Corcoran Group, there were 52 percent fewer closings in Manhattan between January and March compared to 2007, and townhouse sales plunged pretty much everywhere. According to Brown Harris Stevens, average prices dove 11 percent (to $1,502,339) and properties took 11 percent longer (108 days) to sell than a year ago.

Jonathan Miller's Prudential Douglas Elliman report says the median sales price for resales (in other words, anything that's not newly built) fell nearly 21 percent — from $852,500 to $675,000, thanks to the ballooning of inventory levels for co-ops and condos. (The number of co-ops available for sale shot up 33 percent; condos, 35 percent.)

Trophy apartments are apparently no longer as prized: Halstead Property reports an 87 percent decline in closings on properties worth over $10 million last year.

And though it might seem like good news that the median sales price for new developments ticked up 10.4 percent since last quarter, don't let that confuse you: "These probably reflect deals closing now that were done months and in some cases years ago," says Sofia Kim, Streeteasy's vice-president of research. The real good news? House-hunting in New York is going to be a lot more fun for first-time buyers than it has been.