Aspen Insurance Holdings yesterday said its insurance operation had recorded the strongest quarterly underwriting performance in company history — but net income plunged due to investment losses.

The Bermuda-based firm recorded underwriting income in its insurance business of $41.8 million for the third quarter of the year.

Aspen chief executive officer Chris O’Kane said: “Our US insurance platform is on track to exceed $600 million of net earned premiums in 2015, together with an expenses ratio of less than 16 per cent, while our international insurance platform demonstrated a significant improvement in underwriting performance.”

He was speaking as Aspen unveiled its quarterly results, which showed profits of $28.2 million — equivalent to 30 cents per share — for the third quarter of the year, down from $37.4 million in the corresponding quarter last year.

Net realised investment losses widened to $40.4 million from a loss of $16.6 million in the third quarter of 2014.

The firm said gross written premiums were up 10.4 per cent to $720.5 million in the third quarter, compared to $652.5 million in the third quarter of last year.

Aspen recorded pre-tax catastrophe losses, net of reinsurance recoveries, of $19.1 million in the third quarter — $2 million more than in the same quarter of 2014.

The reinsurance segment of the business logged gross written premiums of $316.6 million, an increase of 28.2 per cent on the $256.9 million reported for the same period last year.

Mr O’Kane said: “At Aspen Re, our teams continued to demonstrate their innovative solutions, deep client relationships and disciplined underwriting.

“This was reflected in significant gross written premium growth, both from new business opportunities and the large pro-rata deals that we noted last quarter.”

And he added: “Across our insurance and reinsurance businesses, we remain focused on building value for clients in our chosen areas of expertise.

“We continue to expect to achieve an 11 per cent operating return on our equity for 2015.”