8. Loss Per Share	6 Months Ended
Jun. 30, 2020
Net loss per share:
Loss Per Share	Basic loss per share is calculated by dividing net loss attributable to common stockholders by the weighted-average number of common shares. Diluted loss per share reflects additional common shares that would have been outstanding if dilutive potential shares of common stock had been issued. Potential shares of common stock that may be issued by the Company include shares of common stock that may be issued upon exercise of outstanding stock options. Under the treasury stock method, the unexercised options are assumed to be exercised at the beginning of the period or at issuance, if later. The assumed proceeds are then used to purchase shares of common stock at the average market price during the period. Basic and diluted loss per common share for the three-month period ended June 30, 2020 was $0.07, and diluted loss per common share excludes the effects of 314,493 common share equivalents, since such inclusion would be anti-dilutive. Basic and diluted loss per common share for the three-month period ended June 30, 2019 was $0.04, and diluted loss per common share excludes the effects of 471,199 common share equivalents, since such inclusion would be anti-dilutive. Basic and diluted loss per common share for the six-month period ended June 30, 2020 was $0.10, and diluted loss per common share excludes the effects of 314,493 common share equivalents, since such inclusion would be anti-dilutive. Basic and diluted loss per common share for the six-month period ended June 30, 2019 was $0.11, and diluted loss per common share excludes the effects of 471,199 common share equivalents, since such inclusion would be anti-dilutive. The common share equivalents consist of common shares issuable upon exercise of outstanding stock options.

8. Loss Per Share

6 Months Ended

Jun. 30, 2020

Basic loss per share is calculated by dividing net loss attributable to common stockholders by the weighted-average number of common shares. Diluted loss per share reflects additional common shares that would have been outstanding if dilutive potential shares of common stock had been issued. Potential shares of common stock that may be issued by the Company include shares of common stock that may be issued upon exercise of outstanding stock options. Under the treasury stock method, the unexercised options are assumed to be exercised at the beginning of the period or at issuance, if later. The assumed proceeds are then used to purchase shares of common stock at the average market price during the period.

Basic and diluted loss per common share for the three-month period ended June 30, 2020 was $0.07, and diluted loss per common share excludes the effects of 314,493 common share equivalents, since such inclusion would be anti-dilutive. Basic and diluted loss per common share for the three-month period ended June 30, 2019 was $0.04, and diluted loss per common share excludes the effects of 471,199 common share equivalents, since such inclusion would be anti-dilutive. Basic and diluted loss per common share for the six-month period ended June 30, 2020 was $0.10, and diluted loss per common share excludes the effects of 314,493 common share equivalents, since such inclusion would be anti-dilutive. Basic and diluted loss per common share for the six-month period ended June 30, 2019 was $0.11, and diluted loss per common share excludes the effects of 471,199 common share equivalents, since such inclusion would be anti-dilutive. The common share equivalents consist of common shares issuable upon exercise of outstanding stock options.