12.Stock-based compensation

The Company measures stock-based compensation expense on the grant date, based on the fair value of the award, and recognizes the expense on a straight-line basis over the requisite service period for awards expected to vest. The Company estimated the grant date fair value of stock options using a Black-Scholes valuation model using the following weighted-average assumptions for the periods indicated:

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The Company granted 248 and 97 stock options during the 39 weeks ended October 31, 2020 and November 2, 2019, respectively. The stock-based compensation expense for stock options was $2,900 and $2,204 for the 13 weeks ended October 31, 2020 and November 2, 2019, respectively. The stock-based compensation expense for stock options was $8,247 and $6,523 for the 39 weeks ended October 31, 2020 and November 2, 2019, respectively. The weighted-average grant date fair value of these stock options was $54.40 and $89.91 for the 39 weeks ended October 31, 2020 and

November 2, 2019, respectively. At October 31, 2020, there was approximately $20,691 of unrecognized stock-based compensation expense related to unvested stock options.

The Company issued 161 and 52 restricted stock units during the 39 weeks ended October 31, 2020 and November 2, 2019, respectively. The stock-based compensation expense for restricted stock units was $5,098 and $3,429 for the 13 weeks ended October 31, 2020 and November 2, 2019, respectively. The stock-based compensation expense for restricted stock units was $14,446 and $9,672 for the 39 weeks ended October 31, 2020 and November 2, 2019, respectively. At October 31, 2020, there was approximately $34,048 of unrecognized stock-based compensation expense related to restricted stock units.

The Company did not issue any performance-based restricted stock units during the 39 weeks ended October 31, 2020. The Company issued 21 performance-based restricted stock units during the 39 weeks ended November 2, 2019. The stock-based compensation expense for performance-based restricted stock units was $386 for the 13 weeks ended October 31, 2020. The stock-based compensation benefit for performance-based restricted stock units was $122 for the 13 weeks ended November 2, 2019. The stock-based compensation expense for performance-based restricted stock units was $286 and $2,979 for the 39 weeks ended October 31, 2020 and November 2, 2019, respectively. At October 31, 2020, there was approximately $613 of unrecognized stock-based compensation expense related to performance-based restricted stock units.