Presented below is a summary of the components used to calculate basic and diluted income per share. The Company applies the two-class method of computing income per share, as nonvested share-based awards that contain nonforfeitable rights to dividends are considered securities which participate in undistributed earnings with common stock. The two-class method requires the calculation of separate income per share amounts for the nonvested share-based awards and for common stock. Income per share attributable to common stock is shown in the table below. Nonvested share-based awards are further discussed in Note 12.



	For the Three Months Ended June 30				For the Six Months Ended June 30
(In thousands, except per share data)	2018		2017		2018		2017
Basic income per common share:
Net income attributable to Commerce Bancshares, Inc.	$	110,330	$	78,960	$	211,314	$	150,464
Less preferred stock dividends	2,250		2,250		4,500		4,500
Net income available to common shareholders	108,080		76,710		206,814		145,964
Less income allocated to nonvested restricted stock	1,139		943		2,260		1,888
Net income allocated to common stock	$	106,941	$	75,767	$	204,554	$	144,076
Weighted average common shares outstanding	105,686		105,583		105,660		105,486
Basic income per common share	$	1.02	$	.71	$	1.94	$	1.36
Diluted income per common share:
Net income available to common shareholders	$	108,080	$	76,710	$	206,814	$	145,964
Less income allocated to nonvested restricted stock	1,136		941		2,254		1,883
Net income allocated to common stock	$	106,944	$	75,769	$	204,560	$	144,081
Weighted average common shares outstanding	105,686		105,583		105,660		105,486
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	343		360		338		389
Weighted average diluted common shares outstanding	106,029		105,943		105,998		105,875
Diluted income per common share	$	1.01	$	.71	$	1.93	$	1.36