Australia's leading insurer was hurt by storms in Queensland and Victoria, about a dozen tornadoes in the U.S., and earthquakes in Christchurch, New Zealand during the first half of the year.

“The record level of catastrophes experienced by the worldwide insurance industry during the first half and the recent fall in risk-free interest rates necessitates that we lower our insurance profit range for the full year,” says Frank O'Halloran, chief executive officer.

QBE says it has purchased additional reinsurance to protect against the continuation of abnormal catastrophe activity for the rest of the year.

Gross premiums earned increased 30 percent to $8.94 billion from recent acquisitions over the last year, QBE says.

QBE says its combined ratio was 95.7, up from 89.7 during the first half of last year. Halloran says QBE is still outperforming its peers, “many of whom have announced combined operating ratios in excess of 100 percent due to the record level of catastrophe claims in the first half.”

Premiums rate increases averaged 3 percent on renewed business during the first half of 2011. For the second half, QBE says it expects overall premium rate increases of about 4 percent.