NEW YORK (Bloomberg) - Aon Corp., the world’s largest insurance broker, rose the most since September after fourth-quarter profit beat analysts’ estimates as a measure of revenue at its main unit climbed at the fastest rate since 2007.Net income rose 17 percent to $231 million, or 67 cents a share, from $198 million, or 69 cents, a year earlier, the Chicago-based broker said in a statement today. Operating income of 84 cents a share beat by three cents the average estimate of 15 analysts surveyed by Bloomberg. So-called organic revenue, which excludes the effect of currency fluctuations and acquisitions, rose by three percent at its retail unit selling coverage.CEO Gregory Case has added payroll and consulting services to the brokerage firm’s list of capabilities to counter the global economic decline that crimped demand for insurance. Aon completed the acquisition of Hewitt Associates Inc. on October 1, helping to boost revenue by 12 percent in 2010.Aon is poised to benefit from “an improving global economy in areas such as employment levels, asset values and corporate revenue”, chief financial officer Christa Davies said in a conference call on Friday.The broker jumped $1.54, The broker jumped $1.54,or 3.3 percent, to $47.70 at 12.55pm in New York Stock Exchange composite trading, the highest price for the shares since 2008. Aon has climbed about 23 percent in the past year.Aon said in October it would cut 1,500 to 1,800 jobs globally as it integrated businesses after the acquisition of Hewitt. US commercial insurance rates fell 5.4 percent in the last three months of 2010 and have dropped every quarter since 2004, according to the Council of Insurance Agents and Brokers.