Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation (Tables)

v3.21.2
Stock-based Compensation (Tables)
 9 Months Ended
Sep. 30, 2021
Share-based Payment Arrangement [Abstract]  
Estimated Fair Value of Stock Option Grants
The fair value of stock option awards granted during the thirty-nine weeks ended September 30, 2021 was estimated using the Black-Scholes-Merton option pricing model with the following weighted-average assumptions:
Thirty-nine Weeks Ended
September 30, 2021
Weighted average fair value per stock option $ 41.75
Risk-free interest rate 0.8%
Expected volatility 48.1%
Expected life (in years) 5.4
Dividend yield —%
Stock Option Activity
The table below summarizes stock option activity for the thirty-nine weeks ended September 30, 2021:
Options Weighted Average Exercise Price
Outstanding at January 1, 2021 3,740,604  $ 20.72 
Granted 66,505  95.68 
Exercised (1,071,838) 10.98 
Forfeited or expired (48,988) 39.03 
Outstanding at September 30, 2021
 2,686,283  $ 26.13 
Vested and exercisable at September 30, 2021
 1,689,127  $ 17.80 
Restricted Stock Unit Activity
The following table summarizes restricted stock unit activity during the thirty-nine weeks ended September 30, 2021:
Restricted Stock Units
Unvested at January 1, 2021 128,220 
Granted 123,362 
Vested (26,968)
Forfeited (12,472)
Unvested at September 30, 2021 212,142 
Restricted Stock Award Activity
The following table summarizes restricted stock award activity during the thirty-nine weeks ended September 30, 2021:
Restricted Stock Awards
Service-based Performance-based Total Stock Return (TSR)
Unvested at January 1, 2021 131,844  160,315  104,456 
Granted 28,814  —  — 
Vested (13,555) —  — 
Forfeited (2,508) —  — 
Unvested at September 30, 2021 144,595  160,315  104,456