Segment Information (Tables)

6 Months Ended

Jun. 30, 2011

Segment Information

Schedule of Segment Reporting Information, by Segment

Three Months	Ameren Missouri		Ameren Illinois		Merchant Generation			Other			Intersegment Eliminations			Consolidated
2011:
External revenues	$	814	$	619	$	347		$	1		$	-		$	1,781
Intersegment revenues		8		4		49			-			(61	)		-
Net income (loss) attributable to Ameren Corporation(a)		90		37		15			(4	)		-			138
2010:
External revenues	$	756	$	644	$	325		$	-		$	-		$	1,725
Intersegment revenues		5		3		60			3			(71	)		-
Net income (loss) attributable to Ameren Corporation(a)		113		46		(2	)		(5	)		-			152
Six Months
2011:
External revenues	$	1,581	$	1,424	$	679		$	1		$	-		$	3,685
Intersegment revenues		13		7		96			1			(117	)		-
Net income (loss) attributable to Ameren Corporation(a)		111		70		35			(7	)		-			209
2010:
External revenues	$	1,433	$	1,553	$	679		$	-		$	-		$	3,665
Intersegment revenues		10		5		134			6			(155	)		-
Net income (loss) attributable to Ameren Corporation(a)		140		81		42			(9	)		-			254
Six Months	Ameren Missouri		Ameren Illinois		Merchant Generation			Other			Intersegment Eliminations			Consolidated
As of June 30, 2011:
Total assets	$	12,527	$	7,154	$	3,861		$	1,324		$	(1,475	)	$	23,391
As of December 31, 2010:
Total assets	$	12,504	$	7,406	$	3,934		$	1,354		$	(1,683	)	$	23,515

(a) Represents net income (loss) available to common stockholders.