American International Group yesterday reported a third-quarter profit of $1.86 billion as gains in the value of its AIA Group Ltd. stake fuelled investment results.That compared to a net loss of $4 billion in the third quarter of 2011. Earnings per share were $1.13, compared to a loss per share of $2.10 last year.It was the fourth-straight profit for AIG, the insurer that counts the US as its largest shareholder.Operating profit, which excludes some investing results, was $1 a share, beating the average estimate of 87 cents in a Bloomberg survey of 20 analysts.AIG Property Casualty Operations' net premiums written rose to $8.71 billion from $8.66 billion in the prior year quarter, and net premiums earned for the quarter declined to $8.75 billion, down from $9.04 billion last year.AIG CEO Robert Benmosche is seeking to improve results at the New York-based company’s units that sell life insurance and property-casualty coverage to attract private shareholders as the US winds down a rescue that began in 2008 and swelled to $182.3 billion, according to Bloomberg.Chartis, the property-casualty unit led by CEO Peter Hancock, posted a pretax profit of $949 million, compared with $551 million a year earlier, as investment income climbed.The global property-casualty insurer spent $1.05 on claims and expenses for every premium dollar it collected, compared with spending $1.06 a year earlier. Catastrophe losses narrowed from a year earlier when Hurricane Irene lashed the US East Coast.Premium revenue at Chartis, the insurer of commercial property, corporate boards, and airplanes, fell about 3.2 percent to $8.75 billion, from $9.04 billion a year earlier.The Treasury Department sold $20.7 billion of its AIG shares in September, cuttings its stake to 16 percent from a majority.AIG has gained 52 percent this year, the best performance among 22 companies in the Standard & Poor’s 500 Insurance Index. The stock has dropped 96 percent since the end of 2007.AIG said last month it reached the final stage of review to be designated a systemically important financial institution, which could lead to regulation by the Fed and tighter capital rules. Prudential Financial Inc., the second-biggest US life insurer, also is in the final review step.