China's economic activity data for July, including retail sales, industrial output and investment, has failed to match expectations, fueling concern over a deeper, longer-lasting slowdown in growth.

But the demise of China's growth has been mistakenly forecast before. Is this time different?

Activity data has been missing forecasts since the beginning of the second quarter, with the weakness raising worries that China's economy is coming closer to a crunch point. It would not be for the first time.