Earnings Per Share

6 Months Ended

Jun. 30, 2021

Earnings per Share

The denominator for basic and diluted earnings per share for the three and six months ended June 30, 2021 and 2020 is as follows:


	Three Months Ended June 30		Six Months Ended June 30
	2021	2020	2021	2020
Denominator for basic earnings per share – weighted-average shares	244.5	252.2	244.8	252.3
Effect of dilutive securities – employee stock options, nonvested restricted stock awards and convertible debentures	2.9	3.2	3.0	3.6
Denominator for diluted earnings per share	247.4	255.4	247.8	255.9

During the three months ended June 30, 2021 and 2020, weighted-average shares related to certain stock options of 0.3 and 1.6, respectively, were excluded from the denominator for diluted earnings per share because the stock options were anti-dilutive. During the six months ended June 30, 2021 and 2020, weighted-average shares related to certain stock options of 0.4 and 1.3, respectively, were excluded from the denominator for diluted earnings per share because the stock options were anti-dilutive.

During the three and six months ended June 30, 2021, we issued approximately 0.0 and 0.9 restricted stock units, respectively, under our stock incentive plans, 0.3 of which vesting is contingent upon us meeting specified annual earnings targets for the three year period of 2021 through 2023. During the three and six months ended June 30, 2020, we issued approximately 0.1 and 1.3 restricted stock units, respectively, under our stock incentive plans, 0.2 of which vesting is contingent upon us meeting specified annual earnings targets for the three year period of 2020 through 2022. The contingent restricted stock units have been excluded from the denominator for diluted earnings per share and will be included only if and when the contingency is met.