The following tables reconcile the denominator and numerator used to compute basic earnings per share (“EPS”) to the denominator and numerator used to compute diluted EPS for the three months ended March 31, 2021 and March 31, 2020. Basic EPS is computed using the weighted average number of shares outstanding during the period and income available to shareholders. Diluted EPS is computed similar to basic EPS, except the income available to shareholders is adjusted to add back interest expense, after tax, related to the Convertible Senior Note, and the weighted average number of shares outstanding is adjusted to reflect the dilutive effects of stock-based awards and shares underlying the Convertible Senior Note.

Convertible Senior Note dilution impact is calculated using the if-converted method which was required upon adoption of ASU 2020-06. As a result, the Company elected to adopt the if-converted method when the Convertible Senior Notes were issued during the third quarter of 2020. In connection with the offerings of the Notes, the Company entered into a convertible note hedge and warrants (see Note 10 Debt and Credit Facilities); however, the convertible note hedge is not considered when calculating dilutive shares given its impact is anti-dilutive. The impact of the bond hedge would offset the dilutive impact of the shares underlying the Convertible Senior Note. The warrants have a strike price above our average share price during the period and are out of the money and not included in the tables below.

Dilutive potential common shares include shares the Company could be obligated to issue from its Convertible Senior Notes and warrants (see Note 10 for further discussion) and stock-based awards. Shares to be provided to the Company from its bond hedge purchased concurrently with the issuance of Convertible Senior Notes are anti-dilutive and are not included in its diluted shares. Anti-dilutive stock-based awards excluded from the calculation of earnings per share for the three months ended March 31, 2021 and March 31, 2020 were 145 and 27,596, respectively.

The weighted average number of shares used to compute basic and diluted EPS were:

	Three Months Ended
	March 31, 2021		March 31, 2020
Basic weighted average number of shares outstanding		102,375,923		100,669,693
Stock-based awards		573,048		229,631
Convertible senior notes		8,916,530		-
Diluted weighted average number of shares outstanding		111,865,501		100,899,324

The net income available to shareholders to compute basic and diluted EPS were (in thousands):

	Three Months Ended
	March 31, 2021		March 31, 2020
Net income attributable to Parsons Corporation		9,039		12,973
Convertible senior notes if-converted method interest adjustment		528		-
Diluted net income attributable to Parsons Corporation		9,567		12,973