The study merely confirms that the changes effected by the new laws are largely irrelevant to rent and vacancy levels outside of Manhattan below 96th Street.

"The survey indicates a market beset with falling demand and oversupply evidenced through increasing vacancy levels and falling take up rates", it said.

As of December 31, 2012, the total market vacancy rate for office and flex space is 11.80%, a 1.40% decrease in vacancy from one year ago, and the lowest overall vacancy level since 2003.

Experts say some increase in vacancy levels was all but inevitable, even if the city's economy had not faltered, because public incentives prompted so much new construction in West Midtown.

"We're close" The good news so far is that interest rates remain low enough that developers are able to carry buildings with significant vacancy levels for longer periods of time without the threat of foreclosure from lenders.

That has helped push the vacancy level for midtown's 225 million square feet of office space up to 14 percent - the highest point in nearly a decade.

FOR the first time in more than five years, owners of prime office buildings in midtown Manhattan are facing higher vacancy levels than those of their downtown counterparts.

"It's not just the vacancy level that helps set the rents, it's the number of people coming to the door," Mr. Costello said.

Only six local authorities (out of 32) have vacancy levels below 10 percent, all of them in Leinster (Dublin and surrounds).

Historically, 15 percent has been considered high, but the office market has never been as stratified as it is today, with vacancy levels ranging widely from one building to the next.