Affiliated Managers Group ( AMG) posted better-than-expected second-quarter earnings Wednesday, despite a hairy quarter for equities markets that weighed on asset inflows.The Boston-based asset management holding company also announced a share buyback plan of up to 5% of its outstanding common stock, a move that other money managers have been reluctant to make. AMG's net income rose to $78.1 million, or 86 cents a share, from $26.2 million, or 63 cents a share, a year earlier. Cash earnings, which exclude items such as amortization, rose to $1.30 a share from $1.13 in the same period last year. Analysts polled by Thomson Financial were expecting cash earnings per share of $1.28. Revenue hit $283.1 million, up 36% from $208.3 million a year ago. "AMG produced solid earnings growth in the second quarter of 2006, notwithstanding a challenging equity market environment. Our organic growth remains strong, as net client cash flows during the quarter were $2.9 billion, driven by the strength and diversity of our Affiliates' product offerings," Sean M. Healey, the company's president and chief executive, said in a statement. Of the asset managers that have reported earnings, none have escaped the effects of a second-quarter stock slide that spurred investors to withdraw money from funds. At AMG, assets under management, a key driver of profits at money management firms, hit $202.26 billion at the end of the second quarter. That was up from roughly $138 billion a year ago but down from the $202.85 billion logged at the end of March. Of the $2.9 billion in second-quarter net cash flows, $2.2 billion went into the company's institutional, mutual fund and high-net-worth channels. AMG has investments in more than two dozen midsized money managers. The company also said it will use cash on its books to buy back shares.