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The bubble in Chinese housing is not found at the bottom of the market. It is at the top. When official media endorses the view that housing is "on a wildly unsustainable path," we can be sure there is a gigantic problem lurking there. Almost no analyst sees home prices falling this year. At the end of 2012, however, there was about 236 million square meters of home supply on the market, about three times the volume of monthly sales. That is manageable perhaps, but the real warning sign is that unsold apartments, as measured by floor space, increased 40% last year. The residential sector can fall fast pulled down by top-end units. The rich buy apartments and often leave them empty, treating them as a store of value. It’s not uncommon to find a single owner with as many as...