Note 7 – Net Income per Common Share

Basic net income per common share is based on the weighted average number of common shares outstanding. Diluted net income per common share is based on the weighted average number of common shares outstanding and potentially dilutive shares. The dilutive effect of employee stock-based compensation is included in the computation of diluted net income per common share. The dilutive effect of stock-based compensation is calculated using the treasury stock method and expected proceeds upon exercise or issuance of the stock-based compensation. The treasury stock method assumes that the proceeds from stock-based compensation are used to purchase the Company’s common stock at the average market price during the period. The following table summarizes the shares, in thousands, used in computing basic and diluted net income per common share:



	Three Months Ended
	March 31,
	2017	2016
Average common shares outstanding during the period for basic computation	177,479	177,104
Dilutive effect of employee stock-based compensation	490	715
Average common shares outstanding during the period for diluted computation	177,969	177,819

For the three months ended March 31, 2017 and 2016, all of the Company’s employee stock options were included in the calculations of diluted net income per share as the calculated cost to exercise the stock options was less than the average market price of the Company’s common stock during these periods.