BlackRock Inc, the world's largest money manager, reported a higher-than-expected quarterly profit on Thursday, benefiting from strong markets and a flow of new money into its exchange-traded funds and retail business. The New York-based asset manager ended the fourth quarter through December 31 with $4.3 trillion in assets, including new money and market gains, surpassing the $4 trillion mark for the first time last year. That asset growth - a 14 percent rise from the end of 2012 - helped drive BlackRock's 24-percent jump in quarterly profit to $841 million, or $4.86 per share, up from $690 million, or $3.93 per share, a year earlier. BlackRock and its peers make money by charging fees as a percentage of assets under management. "They are well positioned to generate solid growth almost regardless of the market environment, given that they have a very broad product offering," said Jason Weyeneth, a New York-based analyst with Sterne, Agee & Leach Inc, focusi