According to the official GDP data, China's growth was 6.9% in 2015, which would be the slowest since 1990. China Activity Proxy (CAP) suggests that the true growth rate has been much weaker, perhaps as low as 4.3% in 2015. However, while sluggish by China's recent standards, even 4.3% would still be a respectable pace of growth anywhere else.

Indeed, much of the recent gloomy commentary about the impact of slower growth in China on the rest of the world misses a number of other key points. First, it was never likely that China could maintain double-digit growth as incomes caught up with those in West. Some slowdown was both inevitable as the economy matured, and desirable as part of rebalancing away from over-investment towards consumption.

Second, China's slowdown is nothing new. Growth peaked in 2007 and had been on a clear downward trend since 2011. Crucially, this has not prevented advanced economies from picking up, or global growth from stabilising.

Third, the much larger size of China's economy means that even much slower rates of growth can deliver big increases in demand from year to year and maintain a high contribution to global growth. Indeed, on the official data at least, the increase in China's GDP in 2015 was practically the same as in 2007, even though the annual growth rate had more than halved.

"To be clear, there are valid concerns over the medium-term outlook for China, including high and rising levels of debt and the damage to credibility caused by botched interference in the equity market and by the poor communication of changes in currency policy. But despite some genuine risks, China's economy is not collapsing. Nor is there much to justify fears that the turmoil in China's equity or currency markets will cause major problems in the rest of the world", notes Capital Economics.