China’s worst flood disaster in 18 years led to $US33 billion ($43.1 billion) in economic losses, according to Impact Forecasting’s monthly Global Catastrophe Recap.

Less than 2% of the overall loss – mostly from floods in the Yangtze River Basin last month – is insured, because coverage in the world’s second-biggest economy remains patchy.

An estimated 7.28 million hectares of cropland and more than 800,000 homes were destroyed, the Aon Benfield subsidiary says.

“While it was expected that China would see above-normal rainfall during the peak monsoon months with such a strong El Nino, the intensity and scope of what transpired from the associated floods were at a magnitude not seen in nearly two decades,” Global Head of Impact Forecasting Adam Podlaha said.

Super Typhoon Nepartak caused at least $US1.5 billion ($2 billion) of economic losses after making separate landfalls in Taiwan and China last month.

Other parts of Asia were also inundated, with heavy monsoon rains in India, Nepal, Pakistan and Indonesia.

In the US, six separate severe convective storms and flash flooding from the east coast to the Rockies left a $US1.5 billion bill last month, with insurers picking up 67% of the total.