WR Berkley has attributed improved second-quarter earnings to rate improvements, a strengthening economy and increased market penetration.

The commercial lines insurer reported a 65% rise in net income to $US180 million ($242 million), while gross written premium grew 3.2% to $US1.95 billion ($2.62 billion).

Net investment income increased nearly 14% to $US153.78 million ($207 million).

The combined operating ratio improved to 94.9% from 95.1% in the corresponding period last year.

“Overall, our underwriting performance was favourable, with a combined operating ratio that was relatively stable,” WR Berkley says. “Our ability to manage volatility was again demonstrated in our results, as the impact of severe convective storm activity in the quarter was very modest.”