On June 7, 2019, we entered into a definitive purchase agreement for approximately $16.6 million in cash. A pre-tax gain of $8.3 million was recognized in connection with this transaction, subject to adjustments for working capital purposes and is classified as Income from discontinued operations in the consolidated statements of operations. In 2020, we concluded final adjustments to the purchase agreement, and we determined no additional proceeds based on the results of operations of the sold business in 2019. There are no other activities recorded in the consolidated statements of operations for the year ended December 31, 2021 and 2020, and no balances recorded in the consolidated balance sheet for the discontinued operations as of December 31, 2021 and 2020.

The associated results of operations are separately reported as Discontinued Operations for all periods presented on the Consolidated Statements of Operations. As such, the results from continuing operations for the Company and segment highlights for Production Enhancement, exclude these discontinued operations.

Selected data for this discontinued business consist of the following (in thousands):


	For the Years Ended December 31,
	2021		2020			2019
Services	$	—	$	—		$	1,165
Product sales		—		—			4,233
Total revenue		—		—			5,398

Cost of services		—		—			690
Cost of product sales		—		—			3,196
Depreciation and amortization		—		—			—
Other expense (income)		—		—			91
Operating income		—		—			1,421
Gain (adjustment) on sale		—		(573	)		8,319
Income (loss) from discontinued operations before income tax		—		(573	)		9,740
Income tax expense (benefit)		—		(149	)		1,907
Income (loss) from discontinued operations	$	—	$	(424	)	$	7,833

Net cash provided by operating activities of discontinued operations for the year ended December 31, 2019 was $0.1 million. There was no net cash provided by operating activities of discontinued operations for the years ended December 31, 2021 and 2020.

Net cash provided by (used in) investing activities of discontinued operations for the years ended December 31, 2020 and 2019 was $(0.2) million and $14.8 million, respectively. There was no net cash provided by investing activities of discontinued operations for the year ended December 31, 2021.