UNAUDITED SELECTED QUARTERLY RESULTS OF OPERATIONS

Summarized below is our unaudited quarterly financial data for the quarters during the years ended December 31, 2018 and 2017 (in thousands, except per share data):



	Quarter ended 2018
	December 31		September 30			June 30			March 31
Services and product sales revenue	$	173,207	$	182,146		$	175,475		$	170,018
Cost of services and product sales	125,694		128,179			123,773			119,318
Other operating expenses (3)	29,535		19,088			18,253			18,384
Operating income	17,978		34,879			33,449			32,316
Interest expense	3,634		3,278			3,296			3,120
Income before income tax expense	14,344		31,601			30,153			29,196
Income tax expense	5,750		9,404			5,020			5,273
Net income from continuing operations	8,594		22,197			25,133			23,923
Net income (loss) from discontinued operations	408		208			(328		)	(346		)
Net income	9,002		22,405			24,805			23,577
Net income (loss) attributable to non-controlling interest	167		(7		)	53			50
Net income attributable to Core Laboratories N.V.	$	8,835	$	22,412		$	24,752		$	23,527

Per share information:
Basic earnings per share (1) (2)	$	0.20	$	0.51		$	0.56		$	0.53
Diluted earnings per share (1) (2)	$	0.20	$	0.50		$	0.56		$	0.53

Weighted average common shares outstanding:
Basic	44,226		44,216			44,203			44,179
Diluted	44,401		44,591			44,493			44,463



	Quarter ended 2017
	December 31			September 30			June 30		March 31
Services and product sales revenue	$	170,111		$	162,887		$	158,212	$	156,609
Cost of services and product sales	119,942			118,361			113,635		113,021
Other operating expenses	17,764			17,857			17,222		20,049
Operating income	32,405			26,669			27,355		23,539
Interest expense	2,717			2,707			2,692		2,618
Income before income tax expense	29,688			23,962			24,663		20,921
Income tax expense	8,016			3,595			3,709		2,929
Net income from continuing operations	21,672			20,367			20,954		17,992
Net income (loss) from discontinued operations	(20		)	686			1,755		(310		)
Net income	21,652			21,053			22,709		17,682
Net income (loss) attributable to non-controlling interest	(39		)	(33		)	19		24
Net income attributable to Core Laboratories N.V.	$	21,691		$	21,086		$	22,690	$	17,658

Per share information:
Basic earnings per share (1) (2)	$	0.49		$	0.48		$	0.51	$	0.40
Diluted earnings per share (1) (2)	$	0.49		$	0.48		$	0.51	$	0.40

Weighted average common shares outstanding:
Basic	44,147			44,141			44,164		44,159
Diluted	44,276			44,332			44,374		44,347


(1)	Basic earnings per share and Diluted earnings per share are based on Net income attributable to Core Laboratories N.V.


(2)	The sum of the individual quarterly earnings per share amounts may not agree with the year-to-date earnings per share amounts as each quarterly computation is based on the weighted average number of common shares outstanding during that period.


(3)	Fourth quarter of 2018 includes charges of $9.9 million of additional stock compensation expenses. See Note 14.