中国政府于2012年初宣布，2011年中国经济增长率略有下降，但仍然保持了令人惊艳的9.2%的高速增长，全球股市对此反映积极。投资者们也仍然看好中国的未来。他们似乎相信了官方的说词——也就是中国巨大的房价泡沫正在渐渐地、平稳地缩小，因此对于中国这个全球经济引擎来说，房地产泡沫破裂的风险可谓微乎其微。

    但是数据却告诉了我们一个不同的故事。国民的买房热情使得房价上涨得太高太快了，日本上世纪90年代那样的房地产崩盘在中国上演几乎已经是板上钉钉的事实。经过官方夸大的经济增长率届时可能会遭受重大打击，中国的经济增长率可能会一路下跌到不堪想象的5%以下。

    在本文的分析中，我会大量引用我在芝加哥大学（University of Chicago）布斯商学院（Booth School of Business）的教授——也是我的良师益友——罗伯特•艾利伯的研究。艾利伯现居住在新罕布什尔州，退休后，他为朋友和客户撰写着一份非常出色的时事通讯。他早于大多数专家发现了不计后果的信贷扩张、巨额的贸易赤字和资产泡沫等问题可能造成的恶果，今天，这些问题确实已经笼罩在欧美经济的头上。

    正如艾利伯所说：“在中国，房地产对经济增长的贡献远远超过人们公认的水平，而且这完全是不可持续发展的。”

    艾利伯有一个学生住在北京，他的遭遇最早让艾利伯意识到中国的房地产泡沫存在破裂的风险。这名学生对艾利伯说，他刚刚搬到了一座公寓楼，这幢楼里有几百套房间，但整栋楼只有他一个住户。其它的房子都被炒房者买走了。

    那年年末，艾利伯来到北京一家高端开发商的办公室。该公司每卖出一套1100平方英尺（约102平方米）的毛坯房就能拿到60万美元。而买房者的年收入大概在2万到3万美元之间。考虑到这些人的收入并不算很高，很显然他们并不是在买一处可以负担得起的新住宅，而是在炒房。他们要么只在那儿住上一阵，然后将房子转手；要么就是空着不住，同时寻找下家，凭空赚取高额差价。

租金 vs. 房价

    中国的房价和租金之巨额落差让艾利伯深深震惊。一般来说，一套价值60万美元的房子如果租出去，刨去各种费用，每个月的租金还不到1000美元（假设无按揭贷款）。吸引投资者的并不是租金收入，而是房价的巨幅飙升，从2008年到去年，房价平均升值了20%到30%不等。

    租金，也就是居住在一套房子里的成本，对于房价有某种下拉作用。这是因为对于同一套房子而言，如果买房成本比租房成本贵很多的话，人们就不会去买房——除非他们认为房价会持续飙升，这是一种纯粹的赌徒心态，而且这种心理是不会持久的。在中国房地产泡沫最严重的市场上，房价达到了年租金的五、六十倍——比如上文中我们讨论过的那个例子。当房价为60万美元，年租金为1.2万美元时，房价与租金比即为50：1。哪怕是美国房市泡沫在2006年达到顶峰时，全国各地的房价租金比也远远没有达到50或60之高。当时，40：1就被认为是极高的比例了。

    那么中国的房价到底要下跌多少，买房成本才能合理地接近租房成本呢？据艾利伯估算，要实现这个目标，租金收益率至少要从目前的少于2%上涨到5%，甚至还要更高一些。

    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.

    租金收益率是指用年租金除以市场价格，就好比债券收益是指用固定利息金额除以该债券的当日价格。美国市场的平均租金收益率在6%左右，意味着房价租金比约为17。中国的租金收益率如果提高到5%，房价将下跌60%。

    艾利伯绝对不是唯一一个预言中国房市将崩盘的经济学家。美国传统基金会（Heritage Foundation）的经济学家史剑道（Derek Scissors）表示：“我估计中国的楼市价格会下跌60%甚至更多，这的确是可能的。”

    房价的调整已经开始了。官方数据显示，从去年年末开始房价出现了适度下降，但众所周知，那些数据是靠不住的。我们不妨看看那些试图卖掉房子的房主们。折价30%卖房的现象并不鲜见。事实上，很多在2010年花了60万美元买房的人都愤怒地发现，开发商现在正在同一幢大楼里以45万美元每套的价格销售那些尚未卖出的房子。

    究竟是什么有可能打击到中国引以为傲的经济增长率？我们不妨重新梳理一下中国炒房热的动力。中国政府对利率、政府债券收益和其它国内投资工具施加了严格的限制。2011年的通胀率超过了5%，而10年期债券收益率仅为3.5%。在中国，你很难找到比通胀跑得更快的投资工具。2008年全球金融危机爆发后，随着货币政策由紧转松，大量过剩现金流到了唯一一个能产生巨额回报的地方——房地产。

    在大约四年多的时间里，中国平均每年新建住房面积10亿平方米，为美国的10倍。而要想满足那些有刚性住房需求的购房者——比如说那些从农村搬到城市里的人，每年只需要7亿平方米足矣。

    所以我们不妨按照这个数据来假设需求水平。另外中国还有700万至800万套闲置的房子。如果每年可卖掉其中的200万套，那么中国每年再建造5亿平方米就够了，这只相当于过去几年每年新建住房面积的一半。新建住房面积的下降不仅会影响住房支出，还会影响钢铁、铜和家用电器的产量。

    根据艾利伯的计算，新建住房量的迅速下跌会使中国经济增长率降低整整5个百分点。在他看来，2011年中国经济增长率虽然高达9 .2%，但其中大概有3个百分点都来自泡沫。考虑那些待售的空房，还要再下调2个点，因此中国未来的增长前景远没有官方预测的那么强劲。

    与后危机时代的美国不同，中国在泡沫破裂后还将继续增长，即便增长步伐速度会放缓很多。届时中国会出台另一个庞大的经济刺激计划来弥补房市崩盘的损失，这个刺激计划的效果值得观察。如果随后再次发生通胀，就需要用减缓经济发展的代价来控制通胀。

    或者就像艾利伯所观察到的那样：“中国以10%的增长率高速发展的日子可能将成为历史。”

    译者：朴成奎

    The rental yield is simply the annual rent divided by the market price, just as the yield on a bond is the fixed interest payment divided by the price of the bond that day. In the U.S., the rental yield averages around 6%, meaning the multiple of prices to rents is around 17. The adjustment to a 5% rental yield in China would push prices down by 60%.

    Aliber is by no means the sole China expert to predict that a steep drop is coming. "I estimate that a decline of 60% or even more is the upper end of the range, but is indeed possible," says Derek Scissors, an economist at the Heritage Foundation.

    The adjustment has already begun. While the government's official figures show modest declines starting late last year, those numbers are famously unreliable. A better view comes from owners trying to sell their units. Losses of 30% aren't uncommon. In fact, many owners who paid, say, $600,000 in 2010 are furious that their landlords are now offering unsold units in the same building for $450,000.

    What's the probable hit to China's vaunted growth rate? It's important to recap the forces that caused the frenzy. China imposes tight restrictions on returns on bank accounts, government bond yields and other domestic investments. Inflation for 2011 exceeded 5%, but 10-year bond yields are just 3.5%. It's extremely difficult to find investments that yield more than inflation. When the easy money policies took charge after the worldwide crash of 2008, the excess cash flowed into the only place with big returns -- real estate.

    For around four years, China has been building around 1 billion square meters of housing a year, ten times the figure in the U.S. The amount needed to accommodate real owners -- people moving from farms to the cities, for example -- is 700 million square meters.

    So let's assume that demand goes back to that level. China is also swamped with seven to eight million vacant units. If around two million of those are sold a year, China will need to build just 500 million square meters annually -- half of the total over the past several years. That decline will pound not just expenditures on apartments, but production of steel, copper and appliances.

    By Aliber's reckoning, the sharp decline in housing production could lower China's growth rate by a full five points. In his view, around three points of its 9.2% growth rate in 2011 came from the bubble. Shave two more points for the empty apartments that need to be sold, and future growth looks far less robust than the official projections.

    Unlike the post-crash U.S., China will keep growing after the bubble bursts, though at a far slower rate. What bears watching is the effect of another gigantic stimulus program to compensate for the decline in housing. If renewed inflation follows, so will a slowdown needed to tame it.

    Or as Aliber observes, "China's spurt of a 10% growth rate is likely to be history."