Common Stock (Tables)

6 Months Ended

Jun. 30, 2011

Common Stock

Summary of Components Used to Calculate Basic and Diluted Income Per Share

	For the				For the
	Three Months				Six Months
	Ended June 30				Ended June 30
(In thousands, except per share data)	2011		2010		2011		2010
Basic income per common share:
Net income attributable to Commerce Bancshares, Inc.	$	69,034	$	59,734	$	129,487	$	103,904
Less income allocated to nonvested restricted stockholders		501		331		905		565
Net income available to common stockholders	$	68,533	$	59,403	$	128,582	$	103,339
Distributed income	$	19,909	$	19,505	$	39,816	$	38,992
Undistributed income	$	48,624	$	39,898	$	88,766	$	64,347
Weighted average common shares outstanding		86,539		87,139		86,504		87,079
Distributed income per share	$	.23	$	.23	$	.46	$	.45
Undistributed income per share		.57		.46		1.03		.74
Basic income per common share	$	.80	$	.69	$	1.49	$	1.19
Diluted income per common share:
Net income attributable to Commerce Bancshares, Inc.	$	69,034	$	59,734	$	129,487	$	103,904
Less income allocated to nonvested restricted stockholders		499		329		902		563
Net income available to common stockholders	$	68,535	$	59,405	$	128,585	$	103,341
Distributed income	$	19,909	$	19,505	$	39,816	$	38,992
Undistributed income	$	48,626	$	39,900	$	88,769	$	64,349
Weighted average common shares outstanding		86,539		87,139		86,504		87,079
Net effect of the assumed exercise of stock-based awards — based on the treasury stock method using the average market price for the respective periods		388		415		378		444
Weighted average diluted common shares outstanding		86,927		87,554		86,882		87,523
Distributed income per share	$	.23	$	.23	$	.46	$	.45
Undistributed income per share		.56		.45		1.02		.73
Diluted income per common share	$	.79	$	.68	$	1.48	$	1.18