As of February 13, 2021, the $250 million 2.500% Senior Notes due April 2021 were classified as short-term in the accompanying Condensed Consolidated Balance Sheets. On March 15, 2021, we repaid the $250 million 2.500% Senior Notes due April 2021 which were callable at par in March 2021.
As of February 13, 2021, we had $2.748 billion of availability under our $2.750 billion revolving credit agreements.
Our adjusted debt to earnings before interest, taxes, depreciation, amortization, rent and share-based compensation expense (“EBITDAR”) ratio was 2.0:1 as of February 13, 2021 and was 2.6:1 as of February 15, 2020. We calculate adjusted debt as the sum of total debt, financing lease liabilities and rent times six; and we calculate adjusted EBITDAR by adding interest, taxes, depreciation, amortization, rent, and share-based compensation expense to net income. Adjusted debt to EBITDAR is calculated on a trailing four quarter basis. For the trailing four quarters ended February 13, 2021, debt was presented net of excess cash of $831.4 million. We target our debt levels to a ratio of adjusted debt to EBITDAR in order to maintain our investment grade credit ratings. We believe this is important information for the management of our debt levels. To the extent EBITDAR continues to grow in future years, we expect our debt levels to increase; conversely, if EBITDAR declines, we would expect our debt levels to decrease. Refer to the “Reconciliation of Non-GAAP Financial Measures” section for further details of our calculation.
Stock Repurchases
From January 1, 1998 to February 13, 2021, we have repurchased a total of 149.0 million shares of our common stock at an aggregate cost of $23.932 billion, including 1.3 million shares of our common stock at an aggregate cost of $1.578 billion during the twenty-four week period ended February 13, 2021.
On December 15, 2020, the Board voted to increase the repurchase authorization by $1.5 billion. This raised the total value of shares authorized to be repurchased to $24.65 billion. Considering cumulative repurchases as of February 13, 2021, we had $717.6 million remaining under the Board’s authorization to repurchase our common stock.
Subsequent to February 13, 2021 we have repurchased 169,396 shares of our common stock at an aggregate cost of $203.0 million.
Off-Balance Sheet Arrangements
Since our fiscal year end, we have canceled, issued and modified stand-by letters of credit that are primarily renewed on an annual basis to cover deductible payments to our casualty insurance carriers. Our total stand-by letters of credit commitment at February 13, 2021, was $163.4 million, compared with $246.9 million at August 29, 2020, and our total surety bonds commitment at February 13, 2021, was $40.6 million, compared with $56.7 million at August 29, 2020.
Financial Commitments
As of February 13, 2021, there were no significant changes to our contractual obligations as described in our Annual Report on Form 10-K for the year ended August 29, 2020.
Reconciliation of Non-GAAP Financial Measures
Management’s Discussion and Analysis of Financial Condition and Results of Operations includes certain financial measures not derived in accordance with GAAP. These non-GAAP financial measures provide additional information for determining our optimal capital structure and are used to assist management in evaluating performance and in making appropriate business decisions to maximize stockholders’ value.
Non-GAAP financial measures should not be used as a substitute for GAAP financial measures, or considered in isolation, for the purpose of analyzing our operating performance, financial position or cash flows. However, we have presented non-GAAP financial measures, as we believe they provide additional information that is useful to investors as it indicates more clearly our comparative year-to-year operating results. Furthermore, our management and the Compensation Committee of the Board use these non-GAAP financial measures to analyze and compare our underlying