金融危機從房價下跌開始，為了拯救房貸問題造成的危機，美國搞了QE1。現在未了增加工作機會，美國QE2,於是美國人又開始努力工作建一堆房子，但又沒那麼多美國人住。美國人工作越多，房子就建得越多，房價跌得越凶。

Memo to Homebuilders: Please Stop Building!

In January, new housing starts rose 14.6 percent from December 2010 to an annualized rate of 596,000. (That's still down 2.6 percent from the rate of December 2009.) That's great news for the builders and the workers who depend on them. And in the accompanying video, Aaron Task and I discuss the housing starts number with John Sauro, president of North Atlantic Mortgage Corp.

But I have a message for the homebuilders of America: For the love of God, please stop building!

Some regions desperately need new housing and housing developments. In the North Dakota oil patch, workers are living in trailers. But does Miami need another condominium tower? Does Phoenix need another subdivision? Does Las Vegas need another gated community? No, no and no. As noted in this Steve Bergsman column on Inman News, an excellent source of real estate information, Miami may have 17-20 months of condominium inventory. And quite apart from the obviously overbuilt areas, data suggest the whole nation is glutted with homes for sale — old and new. Many factors are placing downward pressure on housing prices — the continuing flood of distressed sales (estimated at 36 percent of existing-home sales in December 2010, according to the National Association of Realtors), rising interest rates, banks requiring higher down payments and the coming reform of Fannie Mae and Freddie Mac, which is likely to push interest rates higher. But the housing market is, at bottom, a market — even if it is one in which there are all sorts of guarantees and wrinkles. In markets, supply and demand are frequently the most significant forces that dictate the direction and level of prices. And in the U.S. housing market, the story remains one of too much supply and too little demand.

Consider the data on new-home sales.  In December 2010, according to the Census Bureau, new homes sold at a rate of 329,000 per year. But there were 190,000 new homes for sale at the end of December — about 6.9 months worth of supply at the current sales rate. (In all of 2010, 321,000 new homes were sold, down 14.2 percent from 375,000 in 2009.) During the height of the housing boom, between 2003 and 2006, more than 1 million homes were built each year. But they were bought quickly. Between 1998 and 2006, there was generally only about four months of inventory on the market at any given time. While the current figure — 6.9 months of inventory — is way down from the 2009 peak of 14 months, it remains at nearly twice the level it was at in the period when new-home prices were rising. New-home sales are a small part of the market. The much larger existing-home sales market tells a similar story. In December, existing-home sales "rose 12.3 percent to a seasonally adjusted annual rate of 5.28 million in December. . . but remain 2.9 percent below the 5.44 million pace in December 2009." In December, 3.56 million existing homes were for sale, representing 8.1 months of supply. While that figure is down from recent highs, it remains elevated by historical standards. According to data provided by NAR, in the boom years of 1999-2005, existing-homes inventory was generally about four months of sales, and never topped five months.

There's more. The Census Bureau reports that home vacancy rates are also at elevated levels. Since 2006, about 2.7 percent of homes owned by homeowners (as opposed to rental properties) have remained vacant. In the early part of the last decade, the homeowner vacancy rate was less than two percent. Given that there are 75 million homeowner properties, a one percent uptick in the vacancy rate means an extra 750,000 vacant homes. Across the board, the ratio between supply and demand is not in the range that has historically been conducive to rising values. So it's no great mystery that existing-home prices fell one percent between December 2009 and December 2010, according to NAR. In many markets and submarkets the numbers are even worse.

In the town where I live, Westport, Ct., 350 homes were sold last year, and there are about 225 homes on the market — about seven months of inventory. That's not bad. But every day on my way to the train station, I pass a lot where a builder is putting up a 10,000-square-foot speculative house that is tentatively priced at $5.8 million. And I wonder: Why? In the town, only 10 homes sold for more than $4.5 million last year.  And yet there are 24 houses currently for sale above that rich, rich asking price, meaning there are 28 months of inventory in that sector.

So what gives? Why do builders persist in adding new supply into glutted markets? Some new home construction is clearly being done at the behest of clients, and hence is risk-free. Some builders are taking a gamble that their new speculative house, or speculative development, will be more attractive than the product languishing on the market. And some feel they have to build. Once builders have invested money to purchase land and start construction, they frequently have no choice but to move forward. Finishing the job is the only prospect they have at recouping their costs and paying back lenders.

Of course, for first-time homebuyers, the excess supply is a blessing. They can shop around, toss in lowball offers and kick the tires of the distressed properties that continue to hit the market. But they're in the minority. For lenders and the majority of homeowners, especially those who are underwater on their mortgages, the excess supply acts as a brake on appreciation.

There has been a lot of talk about policy measures that would help stabilize the housing market. While large-scale mortgage modification and foreclosure reform would help, salvation will ultimately come from the fundamentals. If demand ramps up rapidly to the point where it removes a lot of inventory from the market, prices could start to firm up. Failing that, we have to count on a decline of new supply. It's only one month of data, but January's housing starts signal it might be on the rise again. And apart from those areas in which housing is desperately needed, the prospect of new supply could prove counterproductive. In some areas, building a new house is like putting a fourth coffee joint at an intersection that already has two Starbucks and one Peet's occupying its corners.