CLB 2018 Annual Report

F-14 Non-controlling Interests We maintain non-controlling interests in several investment ventures and disclose such interests clearly as a portion of equity separate from the parent's equity. The amount of consolidated net income attributable to these non-controlling interests is also clearly presented on the Consolidated Statements of Operations. In addition, when a subsidiary is deconsolidated, any retained non-controlling equity investment in the former subsidiary will be initially measured at fair value and recorded as a gain or loss. Stock-Based Compensation We have two stock-based compensation plans, as described in further detail in Note 14 - Stock-Based Compensation . For new awards issued and awards modified, repurchased or canceled, the compensation expense is equal to the fair value of the award at the date of the grant and is recognized in the Consolidated Statements of Operations for those awards earned over the requisite service period of the award. Earnings Per Share We compute basic earnings per common share by dividing net income attributable to Core Laboratories N.V. by the weighted average number of common shares outstanding during the period. Diluted earnings per common and potential common share include additional shares in the weighted average share calculations associated with the incremental effect of dilutive restricted stock awards and contingently issuable shares, as determined using the treasury stock method. The following table summarizes the calculation of weighted average common shares outstanding used in the computation of diluted earnings per share for the years ended December 31, 2018, 2017 and 2016 (in thousands): 2018 2017 2016 Weighted average basic common shares outstanding 44,206 44,153 43,479 Effect of dilutive securities: Performance shares 221 69 127 Restricted stock 47 42 64 Weighted average diluted common and potential common shares outstanding 44,474 44,264 43,670 3. CONTRACT ASSETS AND LIABILITIES The balance of contract assets and contract liabilities consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Contract assets Current $ 1,145 $ 325 Non-Current 188 — $ 1,333 $ 325 Contract Liabilities Current $ 5,963 $ 2,252 Non-current 1,401 4,442 $ 7,364 $ 6,694 We did not recognize any impairment losses on our receivables and contract assets for the year ended December 31, 2018. Estimate of when contract liabilities will be recognized within 12 months $ 5,963 within 12 to 24 months 1,247 greater than 24 months 154