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Exhibit 12(b)

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 ratios)			2005		2004		2003		2002		2001
Income from continuing operations before provision for income taxes and minority interest			$	965	$	827	$	1,074	$	787	$	306
Less: Earnings from unconsolidated entities under the equity method of accounting				7		34		49		19		(139	)
Add back fixed charges:
	Interest on indebtedness (1)			125		136		101		124		127
	Interest credited on deposit-type insurance contracts			—		1		—		29		56
	Portion of rents representative of interest factor			71		73		67		59		57
		Income as adjusted	$	1,154	$	1,003	$	1,193	$	980	$	685
Fixed charges and preferred stock dividends:
	Interest on indebtedness (1)		$	125	$	136	$	101	$	124	$	127
	Preferred stock dividends (2)			3		3		61		58		70
		Interest and dividends		128		139		162		182		197
	Interest credited on deposit-type insurance contracts			—		1		—		29		56
	Portion of rents representative of interest factor			71		73		67		59		57
		Total fixed charges and preferred stock dividends	$	199	$	213	$	229	$	270	$	310
Ratio of earnings to combined fixed charges and preferred stock dividends				5.8		4.7		5.2		3.6		2.2

(1)

As a result of the adoption of FIN 46 on December 31, 2003, Aon was required to deconsolidate its 8.205% mandatorily redeemable preferred capital securities. This decrease was offset by an increase in notes payable. Beginning in 2004, interest expense ($58 million for both the years ended December 31, 2005 and 2004) on these notes payable is reported as part of interest expense in the consolidated statements of income.

(2)

Included in preferred stock dividends are $57 million and $54 million for the years ended December 31, 2003 and 2002, respectively, and $66 million for the year ended December 31, 2001 of pretax distributions on the capital securities which are classified as "minority interest" on the consolidated statements of income.

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Exhibit 12(b)

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