Economists the world over have been parsing over China’s economic data for years to see if the government has been “adding water” – to use the Chinese phrase – to boost growth numbers. The consensus is that although the numbers of provincial governments don’t always add up, China’s economic data have been getting better.

With investment now making up roughly half of GDP growth, Stephen Green of Standard Chartered undertook to find an appropriate proxy to credit growth as a leading indicator of investment.

Other economists have done this with GDP data, using proxies like electricity consumption and freight movement to see if the bigger numbers make sense. Green sought to use data on sales of excavators and wheel-loaders and cement production as clues to the way investment is headed over the next few months.