????中國政府于2012年初宣布，2011年中國經(jīng)濟增長率略有下降，但仍然保持了令人驚艷的9.2%的高速增長，全球股市對此反映積極。投資者們也仍然看好中國的未來。他們似乎相信了官方的說詞——也就是中國巨大的房價泡沫正在漸漸地、平穩(wěn)地縮小，因此對于中國這個全球經(jīng)濟引擎來說，房地產(chǎn)泡沫破裂的風險可謂微乎其微。

????但是數(shù)據(jù)卻告訴了我們一個不同的故事。國民的買房熱情使得房價上漲得太高太快了，日本上世紀90年代那樣的房地產(chǎn)崩盤在中國上演幾乎已經(jīng)是板上釘釘?shù)氖聦崱＝?jīng)過官方夸大的經(jīng)濟增長率屆時可能會遭受重大打擊，中國的經(jīng)濟增長率可能會一路下跌到不堪想象的5%以下。

????在本文的分析中，我會大量引用我在芝加哥大學（University of Chicago）布斯商學院（Booth School of Business）的教授——也是我的良師益友——羅伯特?艾利伯的研究。艾利伯現(xiàn)居住在新罕布什爾州，退休后，他為朋友和客戶撰寫著一份非常出色的時事通訊。他早于大多數(shù)專家發(fā)現(xiàn)了不計后果的信貸擴張、巨額的貿(mào)易赤字和資產(chǎn)泡沫等問題可能造成的惡果，今天，這些問題確實已經(jīng)籠罩在歐美經(jīng)濟的頭上。

????正如艾利伯所說：“在中國，房地產(chǎn)對經(jīng)濟增長的貢獻遠遠超過人們公認的水平，而且這完全是不可持續(xù)發(fā)展的。”

????艾利伯有一個學生住在北京，他的遭遇最早讓艾利伯意識到中國的房地產(chǎn)泡沫存在破裂的風險。這名學生對艾利伯說，他剛剛搬到了一座公寓樓，這幢樓里有幾百套房間，但整棟樓只有他一個住戶。其它的房子都被炒房者買走了。

????那年年末，艾利伯來到北京一家高端開發(fā)商的辦公室。該公司每賣出一套1100平方英尺（約102平方米）的毛坯房就能拿到60萬美元。而買房者的年收入大概在2萬到3萬美元之間。考慮到這些人的收入并不算很高，很顯然他們并不是在買一處可以負擔得起的新住宅，而是在炒房。他們要么只在那兒住上一陣，然后將房子轉手；要么就是空著不住，同時尋找下家，憑空賺取高額差價。

租金 vs. 房價

????中國的房價和租金之巨額落差讓艾利伯深深震驚。一般來說，一套價值60萬美元的房子如果租出去，刨去各種費用，每個月的租金還不到1000美元（假設無按揭貸款）。吸引投資者的并不是租金收入，而是房價的巨幅飆升，從2008年到去年，房價平均升值了20%到30%不等。

????租金，也就是居住在一套房子里的成本，對于房價有某種下拉作用。這是因為對于同一套房子而言，如果買房成本比租房成本貴很多的話，人們就不會去買房——除非他們認為房價會持續(xù)飆升，這是一種純粹的賭徒心態(tài)，而且這種心理是不會持久的。在中國房地產(chǎn)泡沫最嚴重的市場上，房價達到了年租金的五、六十倍——比如上文中我們討論過的那個例子。當房價為60萬美元，年租金為1.2萬美元時，房價與租金比即為50：1。哪怕是美國房市泡沫在2006年達到頂峰時，全國各地的房價租金比也遠遠沒有達到50或60之高。當時，40：1就被認為是極高的比例了。

????那么中國的房價到底要下跌多少，買房成本才能合理地接近租房成本呢？據(jù)艾利伯估算，要實現(xiàn)這個目標，租金收益率至少要從目前的少于2%上漲到5%，甚至還要更高一些。

????The Chinese government's announcement last week that growth for 2011 slowed only slightly to a still impressive 9.2% was greeted enthusiastically by the world's stock markets. Investors also remain buoyant on China's future. They appear to be buying the official line that the gigantic property price bubble is gradually and smoothly deflating, posing little risk to an engine that's so crucial to the future of global trade.

????But the math tells a different story. The housing frenzy has driven prices so high, so fast, that a crash on the scale of the real estate collapse in Japan in the 1990s is a virtual certainty. And China's already exaggerated official growth rate could take a pounding, all the way to the zone of the unthinkable, into the low single-digits.

????For this analysis, I'll borrow heavily from my former professor and mentor at the University of Chicago's Booth School of Business, Robert Aliber. Affectionately known to his students by his initials "RZA," Aliber is now retired to New Hampshire, but he writes a superb newsletter for his friends and clients. He spotted the reckless credit expansion, huge trade deficits and asset bubbles that now haunt both the U.S. and European economies long before most experts.

????As Aliber puts it, "In China, the housing boom is a far bigger source of growth than is widely recognized, and it's totally unsustainable."

????Aliber got his first clue that the craze spelled disaster from a former student living in Beijing. The young Chicago alumnus told Aliber that he'd just moved into an apartment building with several hundred units, and was the only one living there. Investors had bought all the other apartments that hadn't sold.

????Later that year, Aliber visited the office of an upscale developer in Beijing, who was getting $600,000 for 1100 square foot units with bare walls. The folks doing the purchasing were earning between $20,000 and $30,000. Given those modest incomes, it was obvious that the buyers weren't purchasing an affordable new residence, but speculating in real estate, either to live there for awhile then flip the unit, or simply leave it vacant while seeking a buyer willing to hand them quick windfall.

Rent vs. price

????What amazed Aliber was the chasm between the prices of the apartments and the rents they fetched. A typical $600,000 unit brought a landlord less than $1000 a month in rent after expenses (assuming no mortgage). It wasn't the rental yields that attracted investors, it was the huge price appreciation, averaging from 20% to 30% from 2008 until last year.

????Rents -- the cost of living in the unit -- exercise a sort of gravitational pull on prices. That's because people won't pay far more to own a home than to rent a similar one, unless they think prices will keep soaring -- a view that's a sure sign of casino mentality, and never lasts. In China, prices in the frothiest markets are fifty or sixty time rents. That's the case with the example we discussed above, where the price is $600,000, and the rent is $12000, a ratio of 50-to-1. The 50 to 60 multiple is far above the level in most U.S. markets at the height of the bubble in 2006; in those heady days, a multiple of 40 was considered giant.

????So how far do China's prices need to fall so that the cost of owning is reasonably close to the level of rents? Aliber reckons that the rental yield on apartments will eventually go from less than 2% to 5%, or even a bit higher.