Lloyd’s insurer Catlin has posted solid figures for the nine months to September 30.

A change in accounting methods to recognise premiums for quota share reinsurance treaties underwritten by the company’s US underwriting hub pushed gross written premium (GWP) up to $US4.1 billion ($4 billion).

On a like-for-like basis, GWP grew 8% compared with the previous corresponding period.

The nine-month period saw 51% of the group’s total GWP written outside the UK.

Catlin says continued rate pressure saw GWP fall for its aerospace business, while an increase in casualty GWP was attributed to the growth of the UK motor portfolio and hardening rates in the US construction sector.

Energy and marine premium volume grew due to new business written and better rates for offshore energy, and property GWP increased thanks to new business and larger lines on some accounts.

GWP from reinsurance business was up 10% due to additional volume underwritten by Catlin Re Switzerland, along with rate increases following last year’s catastrophes.

Catlin says average weighted premium rates across the group’s underwriting portfolio increased 5% in the nine-month period, with catastrophe-exposed business up 9% and non-catastrophe classes up 2%.

“The rating environment remains good,” Group CEO Stephen Catlin said. “Average weighted premium rates for catastrophe-exposed business have increased substantially during 2012, while rates for many non-catastrophe classes of business, including US casualty business, continue to rise.”

Catlin experienced no catastrophe losses in the period. It says it is too early to estimate losses from Superstorm Sandy and it expects to update the market at its full-year results.