Net Loss Per Share (Tables)

6 Months Ended

Jun. 30, 2022

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Numerator:
Net loss attributable to common stockholders ($ in millions)	$	(67.9)	$	(55.6)	$	(142.7)	$	(104.6)
Denominator:
Weighted average common shares outstanding — basic and diluted	61,816,225		61,444,958		61,757,722		60,643,764
Net loss per share attributable to common stockholders — basic and diluted	$	(1.10)	$	(0.90)	$	(2.31)	$	(1.72)

Antidilutive potential common shares

The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect.


	Six Months Ended June 30,
		2022	2021
Options to purchase common stock		8,904,546	6,034,609
Unvested restricted stock		837,289	55,129
Total		9,741,835	6,089,738