14. Earnings per share

Earnings per share (“EPS”) are computed on a basic and diluted basis. Basic EPS is computed by dividing net income (less preferred stock dividends) available to common stockholders by the weighted average number of common shares outstanding during the period. The computation of diluted EPS assumes the issuance of common shares for all potential common shares outstanding during the reporting period and, if dilutive, the effect of stock options as computed under the treasury stock method.

The following summarizes information related to the computation of basic and diluted EPS:

	Year Ended December 31,
	2017		2016		2015
Net income attributable to Consolidated Water Co. Ltd. stockholders	$	6,144,062	$	3,960,501	$	7,518,701
Less: preferred stock dividends		(11,418)		(11,563)		(12,028)
Net income available to common shares in the determination of basic earnings per common share	$	6,132,644	$	3,948,938	$	7,506,673

Weighted average number of common shares in the determination of basic earnings per common share attributable to Consolidated Water Co. Ltd. common stockholders		14,896,944		14,809,909		14,741,748
Plus:
Weighted average number of preferred shares outstanding during the period		35,765		37,706		38,612
Potential dilutive effect of unexercised options		73,972		96,413		47,395
Weighted average number of shares used for determining diluted earnings per common share attributable to Consolidated Water Co. Ltd. common stockholders		15,006,681		14,944,028		14,827,755