Net Loss Per Common Share (Tables)

6 Months Ended

Jun. 30, 2020

Net Loss Per Common Share

Shares Outstanding Excluded from Calculation of Diluted Net Loss Per Share

The shares outstanding at the end of the respective periods presented in the table below were excluded from the calculation of diluted net loss per share due to their anti-dilutive effect (in thousands):

	Three and six months ended June 30,
	2020	2019
Common shares under option plans	4,156	3,133
Convertible senior notes	25,648	8,584
Total potential dilutive shares	29,804	11,717