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Exhibit 12(a)

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

			Years Ended December 31,
(millions except ratios)			2006		2005		2004		2003		2002
					As Restated		As Restated		As Restated		As Restated
					(1)		(1)		(1)		(1)
Income from continuing operations before provision for income taxes and minority interest			$	920	$	808	$	733	$	960	$	676
Less: Earnings from unconsolidated entities under the equity method of accounting				4		7		34		49		19
Add back fixed charges:
	Interest on indebtedness (2)			129		125		136		101		124
	Interest credited on deposit-type insurance contracts			—		—		1		—		29
	Portion of rents representative of interest factor			79		71		73		67		59
		Income as adjusted	$	1,124	$	997	$	909	$	1,079	$	869
Fixed charges:
	Interest on indebtedness (2)		$	129	$	125	$	136	$	101	$	124
	Interest credited on deposit-type insurance contracts			—		—		1		—		29
	Portion of rents representative of interest factor			79		71		73		67		59
		Total fixed charges	$	208	$	196	$	210	$	168	$	212
Ratio of earnings to fixed charges				5.4		5.1		4.3		6.4		4.1

(1)

See Note 2 "Restatement of Consolidated Financial Statements."

(2)

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 the years ended December 31, 2006, 2005 and 2004) on these notes payable is reported as part of interest expense in the consolidated statements of income.

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Exhibit 12(a)

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