Earnings (Loss) Per Share

The Company computes basic earnings (loss) per share by dividing net income (loss) by the weighted-average common shares outstanding during the year. Diluted earnings (loss) per share is calculated to give effect to all potentially dilutive common shares that were outstanding during the year. Weighted-average diluted common shares outstanding primarily reflect the additional shares that would be issued upon the assumed exercise of stock options and the assumed vesting of unvested share awards. The treasury stock method has been used to compute diluted earnings (loss) per share for 2019 and 2018.

The Company issued warrants that represent the right to purchase shares of Common Stock, SARs and RSAs, all of which have been evaluated for their potentially dilutive effect under the treasury stock method. See Note 3. Weichai Transactions for additional information on the Weichai Warrants and Note 13. Stock-Based Compensation for additional information on the SARs and the RSAs.

The computations of basic and diluted earnings (loss) per share are as follows:



(in thousands, except per share basis)	For the Year Ended December 31,
	2019		2018
Numerator:
Net income (loss) – basic and diluted	$	8,248	$	(54,726	)

Denominator:
Shares used in computing net income (loss) per share
Weighted-average common shares outstanding - basic	21,512		18,585
Effect of dilutive securities	18		—
Weighted-average common shares outstanding – diluted	21,530		18,585

Earnings (loss) per common share
Earnings (loss) per share of common stock – basic	$	0.38	$	(2.94	)
Earnings (loss) per share of common stock – diluted	$	0.38	$	(2.94	)

The aggregate number of shares excluded from the diluted earnings (loss) per share calculations because they would have been anti-dilutive were 1.4 million and 3.9 million shares in 2019 and 2018, respectively.