China plans to build 20 cities a year for the next 20 years. The unacknowledged problem is finding buyers for those hundreds of millions of new homes.

Last year we published images of ghost cities based on a report from Forensic Asia Limited. This week we asked analyst Gillem Tulloch what has happened in the past six months.

"China built more of them," Tulloch said. "China consumes more steel, iron ore and cement per capita than any industrial nation in history. It's all going to railways that will never make money, roads that no one drives on and cities that no one lives in."

"It's like walking into a forest of skyscrapers, but they're all empty," he said of Chenggong.

Tulloch described a recent visit to a fishing village near Hong Kong, where new apartments are selling for up to $80,000. "People there were joking that no one in Denaya could afford to live there," he said. If these apartments sell at all, it is to speculators.