Aon (AON) 8-K Regulation FD Disclosure

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Exhibit 99.5

AON CORPORATION
SEGMENTS AS RECLASSIFIED—EXCLUDING PREVIOUSLY REPORTED SPECIAL & UNUSUAL CHARGES

			2002															2003
			1st Qtr.			2nd Qtr.			3rd Qtr.			4th Qtr.			Full Year			1st Qtr.
			(millions)
REVENUE
	Risk & Insurance Brokerage Services		$	1,157		$	1,215		$	1,247		$	1,354		$	4,973		$	1,374
	Consulting			233			248			269			304			1,054			282
	Insurance Underwriting			649			750			718			684			2,801			709
	Corporate & Other			49			(91	)		12			24			(6	)		35
	Intersegment Revenues			—			—			—			—			—			(12	)
		Total Revenue	$	2,088		$	2,122		$	2,246		$	2,366		$	8,822		$	2,388
INCOME (LOSS) BEFORE INCOME TAXES
	Risk & Insurance Brokerage Services		$	189		$	138		$	191		$	238		$	756		$	230
	Consulting			27			23			26			44			120			20
	Insurance Underwriting			73			5			41			44			163			63
	Corporate & Other			(13	)		(153	)		(59	)		(48	)		(273	)		(20	)
		Total Income Before Income Taxes	$	276		$	13		$	199		$	278		$	766		$	293
INCOME BEFORE INCOME TAXES—MARGINS
	Risk & Insurance Brokerage Services			16.3	%		11.4	%		15.3	%		17.6	%		15.2	%		16.7	%
	Consulting			11.6	%		9.3	%		9.7	%		14.5	%		11.4	%		7.1	%
	Insurance Underwriting			11.2	%		0.7	%		5.7	%		6.4	%		5.8	%		8.9	%
		Total Income Before Income Taxes—Margins		13.2	%		0.6	%		8.9	%		11.7	%		8.7	%		12.3	%

AON CORPORATION
SEGMENTS AS RECLASSIFIED—EXCLUDING PREVIOUSLY REPORTED SPECIAL & UNUSUAL CHARGES

			2001
			1st Qtr.			2nd Qtr.			3rd Qtr.			4th Qtr.			Full Year
			(millions)
REVENUE
	Risk & Insurance Brokerage Services		$	1,052		$	1,083		$	1,030		$	1,198		$	4,363
	Consulting			212			229			232			265			938
	Insurance Underwriting			628			609			641			643			2,521
	Corporate & Other			(81	)		(4	)		9			(70	)		(146	)
		Total Revenue	$	1,811		$	1,917		$	1,912		$	2,036		$	7,676
INCOME (LOSS) BEFORE INCOME TAXES
	Risk & Insurance Brokerage Services		$	198		$	190		$	150		$	193		$	731
	Consulting			25			30			29			49			133
	Insurance Underwriting			69			83			90			85			327
	Corporate & Other			(172	)		(93	)		(83	)		(158	)		(506	)
		Total Income Before Income Taxes	$	120		$	210		$	186		$	169		$	685
INCOME BEFORE INCOME TAXES—MARGINS
	Risk & Insurance Brokerage Services			18.8	%		17.5	%		14.6	%		16.1	%		16.8	%
	Consulting			11.8	%		13.1	%		12.5	%		18.5	%		14.2	%
	Insurance Underwriting			11.0	%		13.6	%		14.0	%		13.2	%		13.0	%
		Total Income Before Income Taxes—Margins		6.6	%		11.0	%		9.7	%		8.3	%		8.9	%

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AON CORPORATION SEGMENTS AS RECLASSIFIED—EXCLUDING PREVIOUSLY REPORTED SPECIAL & UNUSUAL CHARGES