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Exhibit 12.2

Aon Corporation and Consolidated Subsidiaries
Combined With Unconsolidated Subsidiaries
Computation of Ratio of Earnings to Combined Fixed Charges
and Preferred Stock Dividends

				Years Ended December 31,
(millions except ratio)				2009		2008		2007		2006		2005
Income from continuing operations before income taxes and noncontrolling interests				$	949	$	879	$	1,023	$	738	$	567
Less: Earnings from unconsolidated entities under the equity method of accounting					11		5		6		5		7
Add back fixed charges:
	Interest on indebtedness				122		126		138		129		125
	Interest on uncertain tax positions				2		—		2		—		—
	Portion of rents representative of interest factor				48		47		75		79		71
		Income as adjusted		$	1,110	$	1,047	$	1,232	$	941	$	756
Fixed charges and preferred stock dividends:
	Interest on indebtedness			$	122	$	126	$	138	$	129	$	125
	Interest on uncertain tax positions				2		—		2		—		—
	Preferred stock dividends				—		—		—		—		3
			Interest and dividends		124		126		140		129		128
	Portion of rents representative of interest factor				48		47		75		79		71
			Total fixed charges and preferred stock dividends	$	172	$	173	$	215	$	208	$	199
Ratio of earnings to combined fixed charges and preferred stock dividends					6.5		6.1		5.7		4.5		3.8

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Aon Corporation and Consolidated Subsidiaries Combined With Unconsolidated Subsidiaries Computation of Ratio of Earnings to Combined Fixed Charges and Preferred Stock Dividends