Arch Capital has reported third-quarter net income of $US247.4 million ($322.53 million), compared with $US74.5 million ($97.13 million) in the corresponding period last year.

The Bermuda-based group’s gross written premium (GWP) increased 7.5% to $US1.28 billion ($1.67 billion), and the combined operating ratio improved from 90.7% to 88%.

Investment income gained 8.6% to $US93.62 million ($122.05 million).

The insurance arm contributed underwriting income of $US21.57 million ($28.12 million), up 0.3%, while reinsurance contributed $US62.41 million ($81.36 million), up 13.7%.

Reinsurance GWP dropped 1.5%, reflecting reductions in casualty, marine and aviation lines “due in part to reductions in premium estimates”.