5. Supplemental Consolidated Financial Statement Information

Other current liabilities (in thousands) consist of the following at December 31, 2019 and 2018:


	December 31,
	2019		2018
Accrued self-insurance reserves	$	2,771	$	2,423
Other accrued expenses and current liabilities		828		1,220
Other current liabilities	$	3,599	$	3,643

Disaggregated Revenues

The Company has one line of business, acquiring and processing seismic data in North America. Our chief operating decision maker (President, CEO, and Chairman of the Board) makes operating decisions and assesses performance based on the Company as a whole. Accordingly, the Company is considered to be in a single reportable segment. The following table presents the Company’s operating revenues (unaudited and in thousands) disaggregated by geographic region:


	Year Ended December 31,
		2019		2018		2017
Operating Revenues
United States	$	129,452	$	137,101	$	134,442
Canada		16,321		17,055		22,090
Total	$	145,773	$	154,156	$	156,532

Deferred Costs (in thousands)

Deferred costs were $6,994 and $2,991 at January 1, 2019 and 2018, respectively. The Company’s prepaid expenses and other current assets at December 31, 2019 and 2018 included deferred costs incurred to fulfill contracts with customers of $2,525 and $6,994, respectively.

Deferred costs at December 31, 2019 compared to January 1, 2019 decreased primarily as a result of the completion of several projects for clients with significant deferred fulfillment costs at January 1, 2019. Deferred cost at December 31, 2018 compared to January 1, 2018 increased primarily as a result of new projects for clients with significant deferred fulfillment costs at December 31, 2018.

The amount of total deferred costs amortized for the years ended December 31, 2019 and 2018 was $38,468 and $36,615, respectively. There were no material impairment losses incurred during these periods.

Deferred Revenue (in thousands)

Deferred revenue was $10,501 and $6,314 at January 1, 2019 and 2018, respectively. The Company’s deferred revenue at December 31, 2019 and 2018 was $3,481 and $10,501, respectively.

Deferred revenue at December 31, 2019 compared to January 1, 2019 decreased primarily as a result of completing multiple large projects for clients throughout the year. Deferred revenue at December 31, 2018 compared to January 1, 2018 increased primarily as a result of new projects for clients with large third party reimbursables where data has not yet been recorded.

Revenue recognized for the year ended December 31, 2019 that was included in the contract liability balance at the beginning of 2019 was $10,501. Revenue recognized for the year ended December 31, 2018 that was included in the contract liability balance at the beginning of 2018 was $5,945. Deferred revenue not recognized during either year relates to projects that have not yet started or were cancelled.