Learning to trust China's economic data

China’s official data often invites scepticism and criticism regarding its accuracy. In fact, most of the statistics are on the whole reliable and useful, though it is true that some are inaccurate due to problems with their methodologies.

The quality of the data has been debated for years, but economists as well as critics agree that the long-run trend suggested by the numbers is approximately correct. “They are reliable enough for economists to draw valid conclusions,” said Hu Yifan, head of research at Haitong Securities International. “Overall, the Chinese official data is directionally correct.”

The official China Statistical Yearbook, published each year since 1981 by the Chinese...