According to a recent study by researchers at the Chinese University of Hong Kong and the University of Chicago, China over-reported its economic growth between 2008 and 2016 by an average of 1.7%.

The discrepancy came from local governments who are rewarded for meeting growth and investment targets, the authors say in a draft paper published by the Brookings Institution. The Beijing-based National Bureau of Statistics, knowing such manipulation well, has been adjusting the local numbers but hasn’t done so sufficiently since 2008, authors Wei Chen, Xilu Chen, Chang-Tai Hsieh and Zheng Song wrote.

They instead use numbers such as tax revenue, satellite night lights, electricity consumption, railway cargo flow, exports and imports -- less likely to be fudged, to predict the actual gross domestic product of the world’s second largest economy. "The revised numbers indicate that the slowdown in Chinese growth since 2008 is more severe than suggested by the official statistics,” they wrote.