(8)	NET INCOME PER COMMON SHARE

Basic and diluted net income per common share based on weighted-average shares outstanding are calculated as follows:

	Income (Numerator)		Shares (Denominator)		Per Share Amount
	(Dollars in thousands, except per share data)
Three Months Ended September 30, 2017
Basic
Income available to common stockholders	$	21,710		31,838,392	$	0.68
Dilutive effect of stock options		—		753,885
Diluted
Income available to common stockholders plus assumed exercises of stock options	$	21,710		32,592,277	$	0.67
Three Months Ended September 30, 2016
Basic
Income available to common stockholders	$	17,982		31,262,188	$	0.58
Dilutive effect of stock options		—		582,230
Diluted
Income available to common stockholders plus assumed exercises of stock options	$	17,982		31,844,418	$	0.57
Nine Months Ended September 30, 2017
Basic
Income available to common stockholders	$	66,942		31,792,270	$	2.11
Dilutive effect of stock options		—		741,949
Diluted
Income available to common stockholders plus assumed exercises of stock options	$	66,942		32,534,219	$	2.06
Nine Months Ended September 30, 2016
Basic
Income available to common stockholders	$	52,054		31,143,980	$	1.67
Dilutive effect of stock options		—		581,580
Diluted
Income available to common stockholders plus assumed exercises of stock options	$	52,054		31,725,560	$	1.64

The following table shows the number and average exercise price of options that were excluded from the computation of diluted net income per common share for each period because the options’ exercise prices were greater than the average market price of the common shares:

	Shares		Average Exercise Price
Three Months Ended September 30, 2017		75,543	$	46.46
Three Months Ended September 30, 2016		283,130		30.32
Nine Months Ended September 30, 2017		39,120		46.10
Nine Months Ended September 30, 2016		366,628		29.87