Item 2. Unregistered Sales of Equity Securities, Use of Proceeds, and Issuer Purchases of Equity Securities

Purchases of equity securities. The following table summarizes our purchases of common stock for the three months ended March 31, 2024:

On February 21, 2014, our board of directors approved our current share repurchase program, authorizing us to acquire up to an aggregate of 20.0 million shares of our common stock. The program allows us to repurchase shares of our common stock from time to time for cash in the open market, or in negotiated or block transactions, as market and business conditions warrant and subject to applicable legal requirements. We are authorized to continue repurchasing shares through June 30, 2024, provided that the program may be accelerated, suspended, delayed or discontinued at any time at the discretion of our board of directors. All share repurchases after February 21, 2014 have been executed under this program. Since approval of the share repurchase program in 2014 through March 31, 2024, we have repurchased a total of 7.7 million shares under this repurchase program for an aggregate of $512.7 million.