Since January 1994, the Federal Reserve Board has permitted depository institutions in the United States to implement so-called retail sweep programs. The essence of these programs is computer software that dynamically reclassifies customer deposits between transaction accounts, which are subject to statutory reserve requirement ratios as high as 10 percent, and money market deposit accounts, which have a zero ratio. Through the use of such software, hundreds of banks have sharply reduced the amount of their required reserves. In some cases, this new level of required reserves is less than the amount that the bank requires for its ordinary, day-to-day business. In the terminology introduced by Anderson and Rasche (1996b), such deposit-sweeping activity has allowed these banks to become "economically nonbound," and has reduced to zero the economic burden ("tax") due to statutory reserve requirements. In this analysis, we examine a large panel of U.S. banks and develop quantitative estimates of the impact of sweep software programs on the demand for bank reserves.