Aspen Insurance Holdings’ net profit fell 37% to $US203.4 million ($265.4 million) last year as a fourth-quarter loss dragged down the result.

CEO Chris O’Kane says the group took action on lines where returns were not expected to meet requirements, while pursuing opportunities for long-term profitable growth.

Gross written premium (GWP) grew 5% to $US3.15 billion ($4.1 billion) for the year, while the combined operating ratio blew out to 98.1% from 91.9%.

For the December quarter, the company fell to a loss of $US71.5 million ($93.3 million) after reporting a profit of $US117.9 million ($153.8 million) in the corresponding period of 2015. GWP fell 4.5% to $US606.1 million ($790.7 million).

Mr O’Kane says the reinsurance business performed strongly last year despite a much higher level of catastrophe losses.

Aspen was formed in Bermuda in 2002. It now has offices and subsidiaries in 10 countries, including Australia.