Segment Information

6 Months Ended

Jun. 30, 2011

Segment Information

Segment Information

NOTE 13 - SEGMENT INFORMATION

Ameren has three reportable segments: Ameren Missouri, Ameren Illinois, and Merchant Generation. The Ameren Missouri segment for Ameren includes all the operations of Ameren Missouri's business as described in Note 1 - Summary of Significant Accounting Policies. The Ameren Illinois Regulated Segment for Ameren includes all of the operations of Ameren Illinois' business as described in Note 1 - Summary of Significant Accounting Policies. The Merchant Generation segment for Ameren consists primarily of the operations or activities of Genco, including EEI, AERG, Medina Valley and Marketing Company. The category called Other primarily includes Ameren parent company activities, Ameren Services, and ATXI.

The following table presents information about the reported revenues and specified items included in Ameren's net income for the three and six months ended June 30, 2011, and 2010, and total assets as of June 30, 2011, and December 31, 2010.

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.