Basic earnings (loss) per share is calculated by dividing net income (loss) attributable to common stockholders by the weighted-average number of common shares and, except for periods with a loss from operations, participating securities outstanding during the period.  Diluted earnings (loss) per share reflects additional common shares that would have been outstanding if dilutive potential common shares had been issued.  Potential common shares that may be issued by the Company include convertible debt, convertible preferred stock, options and warrants.

Diluted earnings (loss) per common share for the six-month periods ended June 30, 2016 and 2015 excludes the effects of 14.7 million and 20.3 million common share equivalents, respectively, since such inclusion would be anti-dilutive.  The excluded shares consist of common shares issuable upon exercise of outstanding stock options and warrants, and upon the conversion of convertible debt and convertible preferred stock.

The Company’s unvested stock awards contain nonforfeitable rights to dividends or dividend equivalents, whether paid or unpaid (referred to as “participating securities”).  Therefore, the unvested stock awards are required to be included in the number of shares outstanding for both basic and diluted earnings per share calculations.  However, due to our loss from operations, 257,000 shares of unvested restricted stock for the three-month and six-month periods ended June 30, 2016, and 550,750 shares of unvested restricted stock for the three-month and six-month periods ended June 30, 2015, respectively, were excluded in determining basic and diluted loss per share because such inclusion would be anti-dilutive.