Basic earnings per common share is computed by dividing net income attributable to Novanta Inc., after redeemable noncontrolling interest redemption value adjustment, by the weighted average number of common shares outstanding during the year. The Company recognizes changes in the redeemable noncontrolling interest redemption value by adjusting the carrying amount of the redeemable noncontrolling interest as of the end of the period to the higher of: (i) the estimated redemption value assuming the end of the period is also the redemption date or (ii) the carrying value without any redemption value adjustments. Such adjustments are recorded in retained earnings in stockholders’ equity instead of net income attributable to Novanta Inc. For both basic and diluted earnings per common share, such redemption value adjustments are included in the calculation of the numerator. For diluted earnings per common share, the denominator also includes the dilutive effect of outstanding restricted stock units, stock options, non-GAAP EPS performance-based restricted stock units and total shareholder return performance-based restricted stock units determined using the treasury stock method. Dilutive effects of attainment-based contingently issuable shares granted to the former Laser Quantum noncontrolling interest shareholders and the non-GAAP EPS performance-based restricted stock units will be included in the weighted average dilutive share calculation when the performance targets have been achieved. The dilutive effects of market-based contingently issuable shares are included in the weighted average dilutive share calculation based on the number of shares, if any, that would be issuable as of the end of the reporting period. For years in which net losses are generated, the dilutive potential common shares are excluded from the calculation of diluted earnings per share as the effect would be anti-dilutive.

The following table sets forth the computation of basic and diluted earnings per share (in thousands, except per share amounts):

	Year Ended December 31,
	2018			2017			2016
Numerators:
Consolidated net income	$	51,095		$	62,307		$	22,003
Less: Net income attributable to noncontrolling interest		(1,986	)		(2,256	)		—
Net income attributable to Novanta Inc.		49,109			60,051			22,003
Redeemable noncontrolling interest redemption value adjustment (see Note 5)		1,781			(20,244	)		—
Net income attributable to Novanta Inc. after adjustment for redeemable noncontrolling interest redemption value	$	50,890		$	39,807		$	22,003

Denominators:
Weighted average common shares outstanding— basic		34,913			34,817			34,694
Dilutive potential common shares		560			463			220
Weighted average common shares outstanding— diluted		35,473			35,280			34,914
Antidilutive common shares excluded from above		4			—			85

Earnings per Common Share Attributable to Novanta Inc.:
Basic	$	1.46		$	1.14		$	0.63
Diluted	$	1.43		$	1.13		$	0.63