Global first-quarter catastrophe losses of $US7.1 billion ($9.9 billion) were 47% below the recent 15-year average, based on preliminary figures, according to the Aon reinsurance market outlook.

Aon says the figure will rise as further losses are realised, but so far it marks the slowest start to a year since 2013.

About $US4 billion ($5.6 billion) of losses were in the US, where a spring storm system last month was a major contributor, while the costliest event was Windstorm Eberhard in Europe, which cost $US1.1 billion ($1.5 billion).

The Townsville flooding was the largest Asia-Pacific event, with losses at $US740 million ($1 billion) to date.

Recent relatively benign conditions follow two significant catastrophe years, with losses totalling more than $US240 billion ($334 billion).

Total reinsurance capital declined 3% to $US585 billion ($814.7 billion) at the end of last year compared with a year earlier.

Traditional equity capital fell 5% to $US488 billion ($679.6 billion), while assets under management in the alternative capital sector grew 9% to $US97 billion ($135.1 billion).

Insurers are continuing to handle claims following major events last year, including the California wildfires, Typhoon Jebi and US hurricanes.

“The macro picture still shows that capital has increased by nearly 30% since 2011 across traditional and non-traditional capital sources and remains adequate for demand in all markets,” Aon says.

The June and July renewals period will have a heavy concentration on Florida and Australia.

“Our expectation is that the industry will continue to find adequate supply in the aggregate, with individual companies seeing renewals directly in response to exposure change, general loss experience and a continued focus on loss estimation and creep from the 2017 and 2018 events.”