3 — Basic and Diluted Net Income per Share

Basic net income per share is based upon the weighted-average number of common shares outstanding during the period. Diluted net income per share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock. The underwriters’ warrants, stock options and restricted stock units granted by us represent the only dilutive effect reflected in diluted weighted-average shares outstanding.

The following table presents the computation of basic and diluted net income per share:


	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
	(unaudited)				(unaudited)
Net income	$	2,088,841	$	1,354,968	$	3,934,406	$	2,196,164
Weighted-average shares outstanding — Basic		11,163,506		10,651,619		11,096,942		10,630,123
Effect of dilutive securities:
Underwriters' warrants		92,898		78,351		96,482		67,533
Stock Options		880,908		1,186,412		938,135		1,174,362
Restricted Stock Units		89,348		95,093		96,390		81,468
Weighted-average shares outstanding — Diluted		12,226,660		12,011,475		12,227,949		11,953,486
Basic net income per share	$	0.19	$	0.13	$	0.35	$	0.21
Diluted net income per share	$	0.17	$	0.11	$	0.32	$	0.18

Stock options and warrants to purchase shares of our common stock and restricted stock units excluded from the calculation of diluted net income per share because the effect would have been anti-dilutive are as follows:


	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2019	2018	2019	2018
	(unaudited)		(unaudited)
Anti-dilutive stock options and restricted stock units	6,639	44,123	6,895	46,039