NEW YORK ( TheStreet) -- Transatlantic Holdings ( TRH) reported flat second-quarter earnings on Monday as net premiums written declined nearly 6%. After the closing bell, the reinsurer said it earned $111 million, or $1.70 per common share, in the latest quarter, down slightly from a profit of $112 million, or $1.68 a share, in the same period a year earlier. Operating income came in at $105 million, or $1.62 a share, for the three months ended June 30, down from $129 million, or $1.93 per share, last year. Revenue fell 1.5% to $1.1 billion in the quarter with net premiums written totaling $947.6 million vs. $1.03 billion last year. Excluding the impact of foreign currency exchange, net premiums written fell 4% year-over-year, Transatlantic said. The mean estimate of analysts polled by Thomson Reuters was for a profit of $1.68 a share in the June period. The latest results reflect the impact of $27 million in pre-tax net costs related to catastrophic events, including $14 million related to the Deepwater Horizon explosion in the Gulf of Mexico involving BP and the impact of an earthquake in Chile. "Transatlantic performed well in the quarter. We grew book value per share by 2.5% and achieved an annualized GAAP ROE of 11%, based on second quarter net income," said Robert Orlich, the company's president and CEO, in a press release. "Our operations were strong and the impact of 2010 catastrophe events modest." The stock closed Monday's session at $48.81, up 59 cents, or 1.2%. Volume of around 300,000 was less than the issue's three-month trailing daily average of nearly 420,000. Year-to-date, shares are down about 7.5%. -- Written by Maria Woehr in New York.