American International Group (AIG) reported a loss of $4.1 billion in the third quarter, widening 64% from a $2.5 billion loss in the year-ago period. The federally bailed-out insurer said in its earnings report released Thursday that quarterly results “were negatively affected by several macroeconomic drivers.” The New York-based firm reported an after-tax operating loss of $3 billion, a significant increase from $114 million in the third quarter 2010. Loss per share was $2.16 for the quarter, narrowing from a loss per share of $18.53 a year earlier. On an operating basis, the loss per share was $1.60, compared to a loss of 84 cents in the year-ago quarter. AIG’s mortgage insurance division had a pre-tax loss of $79 million in the third quarter, narrowing from $127 million a year ago. “AIG continues to navigate a challenging global economic environment, and our results for the quarter were adversely affected by equity market declines, widening credit spreads and declining rates, as well as property catastrophe losses,” President and CEO Robert Benmosche said. Catastrophe losses amounted to $574 million, including $372 million from Hurricane Irene, for the quarter. The storm struck the East Coast in late August, and an early estimate said damage could cost $7 billion, according to The New York Times. The company repaid $972 million in bailouts to the Treasury Department earlier this week. It still owes $50 billion of the $182 billion provided to it during the financial crisis. Write to Andrew Scoggin. Follow him on Twitter @ascoggin.