Swiss Re’s property and casualty reinsurance business recorded a $US413 million ($527 million) net loss last year, hit by $US3.7 billion ($4.72 billion) of claims arising from natural disasters including Cyclone Debbie.

The division made a $US2.1 billion ($2.68 billion) net profit in 2016.

It reported a fall in gross written premium (GWP) last year to $US16.54 billion ($21.12 billion) from $US18.15 billion ($23.17 billion), while the combined operating ratio blew out to 111.5% from 93.5%.

Swiss Re’s group net profit plummeted to $US331 million ($422.56 million) from $US3.56 billion ($4.54 billion), and GWP fell to $US34.78 billion ($44.4 billion) from $US35.62 billion ($45.47 billion).

Debbie, hurricanes in the US and Caribbean, Mexican earthquakes and California wildfires produced about $US4.7 billion ($6 billion) in claims net of retrocession and before tax.