Earnings per Share

Basic earnings per share are calculated by dividing net income available to common stockholders by the weighted average number of common shares outstanding (including participating securities) during the year. The Company's only participating securities are unvested restricted stock awards that contain non-forfeitable rights to dividends. See Note 9, "Stockholders' Equity," under the caption "Shares Authorized and Share Issuance," to the Company's unaudited consolidated interim financial statements of this Form 10-Q above for further information regarding the Company's participating securities. Diluted earnings per share reflects the effect on weighted average shares outstanding of the number of additional shares outstanding if dilutive stock options were converted into common stock using the treasury stock method.

The table below presents the increase in average shares outstanding, using the treasury stock method, for the diluted earnings per share calculation for the periods indicated:



	Three months ended March 31,
	2020	2019
Basic weighted average common shares outstanding	11,841,392	11,730,482
Dilutive shares	35,639	52,923
Diluted weighted average common shares outstanding	11,877,031	11,783,405

There were 75,545 and 52,478 stock options outstanding for the three months ended March 31, 2020 and March 31, 2019, respectively that were determined to be anti-dilutive and therefore excluded from the calculation of dilutive shares for those periods. These stock options, which were not dilutive at those dates, may potentially dilute earnings per share in the future.