These notes apply to the consolidated financial statements of Natural Gas Services Group, Inc. (the "Company", “NGSG”, "Natural Gas Services Group", "we" or "our") (a Colorado corporation). Natural Gas Services Group was formed on December 17, 1998 for the purposes of combining the operations of certain manufacturing, service and leasing entities. The accompanying consolidated financial statements include the accounts of the Company, its subsidiary, NGSG Properties, LLC and the rabbi trust associated with the Company’s deferred compensation plan, see Note 5. All significant intercompany accounts and transactions for the periods presented have been eliminated in consolidation.

Natural Gas Services Group is a leading provider of small to medium horsepower compression equipment to the natural gas industry, with an emerging position in the large horsepower market. We focus primarily on the non-conventional natural gas and oil production business in the United States (such as coal bed methane, gas shale, tight gas and oil shale). We manufacture, fabricate and rent natural gas compressors that enhance the production of natural gas wells. NGSG provides maintenance services for its natural gas compressors. In addition, we sell custom fabricated natural gas compressors to meet customer specifications dictated by well pressures, production characteristics and particular applications. We also manufacture and sell flare systems for oil and natural gas plant and production facilities.

The preparation of our consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires our management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Significant estimates include fixed asset lives, bad debt allowance and the allowance for inventory obsolescence. Additionally, NGS conducts a yearly review of impairment of long-lived assets. Throughout the review, determining factors are based on estimates that can significantly impact the carrying value of these assets. It is at least reasonably possible these estimates could be revised in the near term and the revisions could be material.

Our trade receivables consist of customer obligations for the sale of compressors and flare systems due under normal trade terms, and operating leases for the use of our natural gas compressors. The receivables are not collateralized except as provided for under lease agreements. However, we typically require deposits of as much as 50% or use of progress payments for large custom sales contracts. We extend credit based on management's assessment of the customer's financial condition, receivable aging, customer disputes and general business and economic conditions. The allowance for doubtful accounts was $291,000 and $569,000 at December 31, 2018 and 2017, respectively. Management believes that the allowance is adequate; however, actual write-offs may exceed the recorded allowance.

The Company applied ASC 606 using the cumulative effect method. We had no significant changes in our recognition of revenue at adoption and our review of all open revenue from contracts with customers on January 1, 2018 indicated we had no adjustment to be made. Therefore, our consolidated financial statements for 2017 reported under ASC 605 are comparable to the consolidated financial statements for 2018 reported under ASC 606, since an adjustment was not needed, except for the respective additional disclosures as detailed below.

Revenue is measured based on a consideration specified in a customer’s contract, excluding any sale incentives and taxes collected on behalf of third parties (i.e. sales and property taxes). We recognize revenue once a performance obligation has been satisfied and control over a product or service has transferred to the customer. Shipping and handling costs incurred are accounted for as fulfillment costs and are included in cost of revenues in our condensed consolidated income statement.

Rental Revenue. The Company generates revenue from renting compressors and flare systems to our customers. These contracts may also include a fee for servicing the compressor or flare during the rental contract. Our rental contracts range from six to twenty-four months, with revenue being recognized over time, in equal payments over the term of the contract. After the terms of the contract have expired, a customer may renew their contract or continue renting on a monthly basis thereafter. In accordance with generally accepted accounting principles, the revenue earned from servicing rental equipment is recognized in accordance with ASC 606, while the revenue earned from the rental of the equipment is recognized in accordance with ASC 840 - Leases.

Custom/fabricated compressors and flare systems - The Company designs and fabricates compressors and flares based on the customer’s specifications outlined in their contract. Though the equipment being built is customized by the customer, control under these contracts does not pass to the customer until the compressor or flare package is complete and shipped, or in accordance with a bill and hold arrangements the customer accepts title and assumes the risk and rewards of ownership. We request some of our customers to make progressive payments as the product is being built; these payments are recorded as a contract liability on the Deferred Income line on the consolidated balance sheet until control has been transferred. These contracts also may include an assurance warranty clause to guarantee the product is free from defects in material and workmanship for a set duration of time; this is a standard industry practice and is not considered a performance obligation.

From time to time, upon the customer’s written request, we recognize revenue when manufacturing is complete and the equipment is ready for shipment. At the customer’s request, we will bill the customer upon completing all performance obligations, but before shipment. The customer will formally request we ship the equipment per their direction from our manufacturing facility at a later specified date and that we segregate the equipment from our finished goods, such that they are not available to fill other orders. Per the customer’s agreement change of control is passed to the customer once the equipment is complete and ready for shipment. We have operated using bill and hold agreements with certain customers for many years, with consistent satisfactory results for both the customer and us. The credit terms on these agreements are consistent with the credit terms on all other sales. All control is shouldered by the customer and there are no exceptions to the customer’s commitment to accept and pay for the manufactured equipment. Revenues recognized related to bill and hold arrangements for the years ended December 31, 2018 and 2017 was approximately $8.3 million and $4.6 million, respectively.

Parts - Revenue is recognized after the customer obtains control of the parts. Control is passed either by the customer taking physical possession or the parts being shipped. The amount of revenue recognized is not adjusted for expected returns, as our historical part returns have been de minimis.

Exchange or rebuilding customer owned compressors - Based on the contract, the Company will either exchange a new/rebuilt compressor for the customer’s malfunctioning compressor or rebuild the customer’s compressor. Revenue is recognized after control of the replacement compressor has transferred to the customer by physical delivery, delivery and installment or shipment of the compressor.

Used compressors or flares - From time to time, a customer may request to purchase a used compressor or flare out of our rental fleet. Revenue from the sale of rental equipment is recognized when the control has passed to the customer, when the customer has taken physical possession or the equipment has been shipped.



	Year Ended December 31,
	(in thousands)
	2018		2017		2016
Compressors - sales	$	10,994	$	13,382	$	10,038
Flares - sales	2,535		2,755		1,183
Other (Parts/Rebuilds) - sales	2,740		4,071		2,400
Service and maintenance ¹	20,537		19,857		24,016
Total revenue from contracts with customers	36,806		40,065		37,637
Add: non-ASC 606 rental revenue	28,672		27,628		34,017
Total revenue	$	65,478	$	67,693	$	71,654


	December 31, 2018		December 31, 2017
	(in thousands)
Accounts Receivable
Accounts receivable - contracts with customers	$	4,353	$	5,454
Accounts receivable - non-ASC 606	3,157		3,649
Total Accounts Receivable	7,510		9,103
Less: Allowance for doubtful accounts	(291)		(569)
Total Accounts Receivable, net	7,219		8,534

Deferred income	$	81	$	185

The Company recognized $176,000 in revenue for the period ended December, 2018 that was included in deferred income at the beginning of 2018. For the period ended December 31, 2017, the Company recognized revenue of $1.9 million from amounts related to sales that were included in deferred income at the beginning of 2017.

The Company applies the transition practical expedient in ASC 606-10-65-1(f)(3) and does not disclose the amount of the transaction price allocated to the remaining performance obligations and an explanation of when the Company expects to recognize that amount as revenue for 2018.

The Company applies the practical expedient in ASC 340-40-25-4 and recognizes the incremental costs of obtaining contracts as an expense when incurred if the amortization period of the assets that the Company otherwise would have recognized is one year or less. These costs are included in selling, general and administrative expense on our consolidated income statement.

Sales and rental income to Occidental Permian, LTD. ("Oxy") in 2018 amounted to 28% of revenue. Sales and rental income to Oxy and Devon Energy Production, Inc. ("Devon") in 2017 amounted to 20% and 15% of revenue, respectively. Sales and rental income to Devon and Oxy in 2016 amounted to 21% and 19% of revenue. No other single customer accounted for more than 10% of our revenues in 2018, 2017 or 2016. Oxy amounted to 26% of our accounts receivable as of December 31, 2018. Oxy amounted to 14% of our accounts receivable as of December 31, 2017. No other customers amounted to more than 10% of our accounts receivable as of December 31, 2018 and 2017.

Inventory (current and long-term) is valued at the lower of cost and net realizable value. The cost of inventories is determined by the weighted average method. A reserve is recorded against inventory balances for estimated obsolescence. This reserve is based on specific identification and historical experience and totaled $19,000 and $15,000 at December 31, 2018 and 2017, respectively. There were 7 newly completed compressor units at December 31, 2018 and December 31, 2017 available for sale or for use in our rental fleet. Our long-term inventory consists of raw materials that remain viable but that the Company does not expect to sell within the next year. At December 31, 2018 and 2017, inventory consisted of the following (in thousands):

Rental equipment and property and equipment are recorded at cost less accumulated depreciation, except for work-in-progress on new rental equipment which is recorded at cost until it’s complete and added to the fleet. At December 31, 2018 and 2017, we had $11.9 million and $6.4 million in rental equipment work-in-progress, respectively. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Our rental equipment has an estimated useful life of 15 years, while our property and equipment has an estimate useful lives which range from three to thirty-nine years. The

We assess the impairment of rental equipment and property and equipment whenever events or changes in circumstances indicate that the net recorded amount may not be recoverable. The following factors could trigger an impairment review: significant underperformance relative to historical or projected future cash flows, significant adverse changes in the extent or manner in which asset is being used or its condition, significant negative industry trends or legislative changes prohibiting us from leasing our units or flares. An impairment loss is recognized if the future undiscounted cash flows associated with the asset and the estimated fair value of the asset are less than the asset's carrying value. We recognized no impairments in years ended December 31, 2018, 2017 or 2016.

Goodwill represents the cost in excess of fair value of the identifiable net assets acquired. Goodwill is tested for impairment annually or whenever events indicate impairment may have occurred. We performed a qualitative analysis each quarter of 2018 and our annual review was performed in the fourth quarter of 2018. We experienced no impairment of goodwill during the years ended December 31, 2018 or 2017.

At December 31, 2018 and 2017, NGSG had intangible assets, which relate to developed technology and a trade name. The carrying amount net of accumulated amortization at December 31, 2018 and 2017 was $1.4 million and $1.5 million, respectively. Developed technology is amortized on a straight-line basis with a useful life of 20 years, with a weighted average remaining life of approximately six years as of December 31, 2018. Amortization expense recognized in each of the years ending December 31, 2018, 2017, and 2016 was $125,000. Estimated amortization expense for the years 2019-2024 is $125,000 per year. NGSG has an intangible asset with a gross carrying value of $654,000 at December 31, 2018 related to the trade name of SCS which was acquired in our acquisition of Screw Compression Systems in January 2005. This asset is not being amortized as it has been deemed to have an indefinite life.


		December 31, 2018										December 31, 2017

	Useful Life (years)	Gross Carrying Value		Accumulated Amortization		Net Book Value		Gross Carrying Value		Accumulated Amortization		Net Book Value



Developed Technology	20	$	2,505	$	1,758	$	747	$	2,505	$	1,633	$	872
Trade Name	Indefinite	654		—		654		654		—		654
Total		$	3,159	$	1,758	$	1,401	$	3,159	$	1,633	$	1,526

Our policy is to periodically review intangibles for impairment through an assessment of the estimated future cash flows related to such assets. In the event that assets are found to be carried at amounts in excess of estimated undiscounted future cash flows, then the assets will be adjusted for impairment to a level commensurate with a discounted cash flow analysis of the underlying assets. Based upon our analysis, we experienced no impairment of intangible assets during the years ended December 31, 2018 or 2017. Separately, we reviewed our indefinite life intangible for impairment with our goodwill qualitative analysis, which we performed each quarter in 2018 due to a continued decline in our rental utilization and then annually in the

We accrue amounts for estimated warranty claims based upon current and historical product warranty costs and any other related information known. The warranty reserve was $22,000 and $65,000 for December 31, 2018 and 2017, respectively, and is included in accrued liabilities on the consolidated balance sheet.

We invest our cash primarily in deposits and money market funds with commercial banks. At times, cash balances at banks and financial institutions may exceed federally insured amounts. We believe that the risk to our cash balance is minimal because we have chosen one of the nation’s largest most successful banks, with strong long-term ratings of Aa2/A+/AA.

Basic earnings per common share is computed using the weighted average number of common shares outstanding during the period. Diluted earnings per common share is computed using the weighted average number of common stock and common stock equivalent shares outstanding during the period. There were anti-dilutive securities in 2018, 2017 and 2016.


	Year Ended December 31,
	2018		2017		2016
Numerator:
Net income	$	426	$	19,851	$	6,469
Denominator for basic net income per common share:
Weighted average common shares outstanding	12,965		12,831		12,702
Denominator for diluted net income per share:
Weighted average common shares outstanding	12,965		12,831		12,702
Dilutive effect of stock options and restricted shares	268		279		233
Diluted weighted average shares	13,233		13,110		12,935
Earnings per common share:
Basic	$	0.03	$	1.55	$	0.51
Diluted	$	0.03	$	1.51	$	0.50

Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases, and operating losses and tax credit carry-forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled.

ASC Topic 740 prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. In order to record any financial statement benefit, we are required to determine, based on technical merits of the position, whether it is more likely than not (a likelihood of more than 50 percent) that a tax position will be sustained upon examination, including resolution of any related appeals or litigation processes. If that step is satisfied, then we must measure the tax position to determine the amount of benefit to recognize in the financial statements. The tax position is measured at the largest amount of the benefit that is greater than 50 percent likely of being realized upon ultimate settlement. We have no uncertain tax positions as of December 31, 2018 or 2017.

On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act (the “2017 Tax Act”), which made broad and complex changes to the U.S. tax code. Certain income tax effects of the 2017 Tax Act are reflected in the Company’s financial results in accordance with Staff Accounting Bulletin No. 118 (“SAB 118”), which provides SEC staff guidance regarding the application of Accounting Standards Codification Topic 740 Income Taxes (“ASC 740”). The effect of this change impacts our effective tax rate. The estimated impact on 2017 was to reduce the deferred tax liabilities by approximately $18.4 million and has been reflected in our effective tax rate reconciliation. At December 31, 2018, we have completed our accounting for the income tax effects of the Tax Act on our deferred tax assets in accordance with the Securities and Exchange Commission Staff Accounting Bulletin No. 118 and ASC 740, and no material adjustments were required.

During the fourth quarter of 2018, the Company discovered a potential uncertain tax position attributable to the deductibility of certain executive compensation expense for federal income tax purposes aggregating approximately $168,000, $149,000 and $230,000 for the years ended December 31, 2017, 2016 and 2015, respectively. As a result, in accordance with ASC Topic 740, during the fourth quarter of 2018, the Company recorded a tax adjustment of $547,000 and accrued penalty and interest expense of $55,000 attributable to the uncertain tax position. Management of the Company determined that effect of the potential uncertain tax position on previously reported results of operations for the years ended December 31, 2017 and 2016 was not material.

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date under current market conditions. ASC Topic 820 established a fair value hierarchy, which requires an entity to maximize the use of observable inputs when measuring fair value. These inputs are categorized as follows:

Level 2- quoted prices in an active market for similar assets or liabilities, inputs other than quoted prices that are observable for similar assets or liabilities, inputs derived principally from or corroborated by observable market data by correlation or other means; and

Management believes that the fair value of our cash and cash equivalents, trade receivables, accounts payable and line of credit at December 31, 2018 and 2017 approximate their carrying values due to the short-term nature of the instruments or the use of prevailing market interest rates.

ASC 280-10-50, “Operating Segments”, define the characteristics of an operating segment as a) being engaged in business activity from which it may earn revenue and incur expenses, b) being reviewed by the company's chief operating decision maker (CODM) for decisions about resources to be allocated and assess its performance and c) having discrete financial information. Although we indeed look at our products to analyze the nature of our revenue, other financial information, such as certain costs and expenses, net income and EBITDA are not captured or analyzed by these categories. Our CODM does not make resource allocation decisions or access the performance of the business based on these categories, but rather in the aggregate. Based on this, management believes that it operates in one business segment.

In their analysis of product lines as potential operating segments, management also considered ASC 280-10-50-11, “Aggregation Criteria”, which allows for the aggregation of operating segments if the segments have similar economic characteristics and if the segments are similar in each of the following areas:

We are engaged in the business of designing and manufacturing compressors and flares. Our compressors and flares are sold and rented to our customers. In addition, we provide service and maintenance on compressors in our fleet and to third parties.These business activities are similar in all geographic areas. Our manufacturing process is essentially the same for the entire Company and is performed in house at our facilities in Midland, Texas and Tulsa, Oklahoma. Our customers primarily consist of entities in the business of producing natural gas. The maintenance and service of our products is consistent across the entire Company and is performed via an internal fleet of vehicles. The regulatory environment is similar in every jurisdiction in that the most impacting regulations and practices are the result of federal energy policy. In addition, the economic characteristics of each customer arrangement are similar in that we maintain policies at the corporate level.

On February 25, 2016, the Financial Accounting Standards Board ("FASB") issued ASU 2016-02, Leases (Topic 842). Under the new guidance, a lessee will be required to recognize assets and liabilities for finance and operating leases with lease terms of more than 12 months. Additionally, this ASU will require disclosures to help investors and other financial statement users better understand the amount, timing, and uncertainty of cash flows arising from leases, including qualitative and quantitative requirements. The ASU initially required a modified retrospective transition method where a company applies the new leases standard at the beginning of the earliest period presented in the financial statements, but in July 2018 the FASB issued ASU 2018-11. ASU 2018-11 added an optional transition method where a company applies the new leases standard at the adoption date and recognizes a cumulative effect adjustment to the opening balance of retained earnings. For public business entities, the amendments are effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted.

The new standard will be adopted by the Company on January 1, 2019. We anticipate applying certain practical expedients provided by ASU 2016-02 that allow companies to not reassess leases that are in effect prior to adoption, the practical expedient in ASU 2018-11 that allows lessors to not separate lease and non-lease components for certain asset classes and the practical expedient in ASU 2018-20 that allows lessors to exclude third party taxes from lease revenue and lease-related expenses. We have reviewed and evaluated the impact the new standard will have on our accounting policies, internal controls and consolidated balance sheet. In our assessment, we determined an increase in lease assets and lease liabilities on the consolidated balance sheet will be approximately $700,000 at adoption. The adoption by the Company of Topic 842, in regards to the increase in liabilities, will not impact the debt covenants on our existing line of credit, as leases are not considered new indebtedness in our credit agreement as confirmed with our bank. The new standard will create an adjustment to retained earnings produced by the difference in lease assets and lease liabilities brought on to the consolidated balance sheet.