According to research by Barry Eichengreen, Donghyun Park, and Kwanho Shin:
That sounds pretty soon! If we look at some numbers of China GDP per capita (source):Using international data starting in 1957, we construct a sample of cases where fast-growing economies slow down. The evidence suggests that rapidly growing economies slow down significantly, in the sense that the growth rate downshifts by at least 2 percentage points, when their per capita incomes reach around $17,000 US in year-2005 constant international prices, a level that China should achieve by or soon after 2015. Among our more provocative findings is that growth slowdowns are more likely in countries that maintain undervalued real exchange rates.
. . . this means that in four or five years (approximately, given the the different base years) China's GDP per capita is going to more than triple [what is missing?]. This is much more than what one would expect from the calculation of the rule of 72, according to which China's GDP per capita will double by 2018 (approximately). China might well be an exception to this rule as well, given its high productivity, and specially high capital accumulation.