Common Stock *

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 March 31
(In thousands, except per share data)	2018		2017
Basic income per common share:
Net income attributable to Commerce Bancshares, Inc.	$	100,984	$	71,504
Less preferred stock dividends	2,250		2,250
Net income available to common shareholders	98,734		69,254
Less income allocated to nonvested restricted stock	1,121		945
Net income allocated to common stock	$	97,613	$	68,309
Weighted average common shares outstanding	105,634		105,389
Basic income per common share	$	.92	$	.65
Diluted income per common share:
Net income available to common shareholders	$	98,734	$	69,254
Less income allocated to nonvested restricted stock	1,118		942
Net income allocated to common stock	$	97,616	$	68,312
Weighted average common shares outstanding	105,634		105,389
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	332		416
Weighted average diluted common shares outstanding	105,966		105,805
Diluted income per common share	$	.92	$	.65

Unexercised stock appreciation rights of 264 thousand and 90 thousand were excluded in the computation of diluted income per common share for the three month periods ended March 31, 2018 and 2017, respectively, because their inclusion would have been anti-dilutive.

* All prior year share and per share amounts in this note have been restated for the 5% common stock dividend distributed in December 2017.