We record the difference between cash paid for stock repurchases and underlying par value as a reduction to additional paid-in capital, to the extent the repurchases does not cause this balance to be reduced below zero, at which point the difference would be recorded as a reduction to accumulated deficit. During fiscal 2020, we repurchased and retired 867,657 shares of common stock at an average purchase price of $17.29 per share for an aggregate repurchase price of $15.0 million. During fiscal 2021, we repurchased and retired 9,526,556 shares of common stock at an average purchase price of $14.17 per share for an aggregate repurchase price of $135.0 million. Repurchase of Common Stock in connection with the Notes Concurrent with the issuance of the Notes (see Note 7), we repurchased and retired 1,008,573 shares, or $20.0 million, of our common stock at $19.83 per share, which was equal to the closing price per share of our common stock on April 4, 2018, the date of the pricing of the offering of the Notes. Note 12. Equity Incentive Plans Equity Incentive Plans We maintain two equity incentive plans: the 2009 Equity Incentive Plan (the 2009 Plan) and the 2015 Equity Incentive Plan (the 2015 Plan). The 2015 Plan serves as the successor to our 2009 Plan and provides for grants of incentive stock options to our employees and non-statutory stock options, stock appreciation rights, restricted stock, RSUs, performance stock awards, performance cash awards, and other forms of stock awards to our employees, directors and consultants. Outstanding awards granted under our 2009 Plan will remain subject to the terms of our 2009 Plan and applicable award agreements, until such outstanding awards that are stock options are exercised, terminated or expired by their terms. Our equity awards generally vest over a two to four year period and expire no later than ten years from the date of grant. We initially reserved 27,000,000 shares of our common stock for issuance under our 2015 Plan. The number of shares reserved for issuance under our 2015 Plan increases automatically on the first day of each fiscal year through 2025, in an amount equal to 5% of the total number of shares of our capital stock outstanding as of the immediately preceding January 31. We net-share settle equity awards held by certain employees by withholding shares upon vesting to satisfy tax withholding obligations. The shares withheld to satisfy employee tax withholding obligations are returned to our 2015 Plan and will be available for future issuance. Payments for employees’ tax obligations to the tax authorities are recognized as a reduction to additional paid-in capital and reflected as a financing activity in our consolidated statements of cash flows. In conjunction with the Portworx acquisition, we assumed (i) certain options to purchase common stock outstanding under Portworx's 2014 Stock Incentive Plan and (ii) RSUs outstanding under the 2020 Portworx Equity Incentive Plan (collectively, the "Assumed Equity Awards"). The Assumed Equity Awards were converted into corresponding awards for shares of our common stock and retained substantially all of the terms and conditions under which they were granted. Approximately 3.9 million shares are reserved for issuance in connection with the Assumed Equity Awards. Refer to Note 4 for further information on the equity awards assumed resulting from the Portworx acquisition. 2015 Amended and Restated Employee Stock Purchase Plan Our 2015 Employee Stock Purchase Plan was amended and restated in fiscal 2020 (2015 ESPP). A total of 3,500,000 shares of common stock was initially reserved for issuance under the 2015 ESPP and an additional 5,000,000 shares of common stock were added in connection with the amendment and restatement. The number of shares reserved for issuance under our 2015 ESPP increases automatically on the first day of February of each of 2016 through 2025, in an amount equal to the lesser of (i) 1% of the total number of shares of our capital stock outstanding as of the immediately preceding January 31, and (ii) 3,500,000 shares of common stock. 83