Banks that remain in the Troubled Asset Relief Program face limited options for exiting the nearly seven-year-old initiative. The Treasury Department still holds securities in 21 banks, compared to 707 when the program was at its height. The ranks have shrunk as banks exit the program or have their shares auctioned off to private investors. Now, many of the banks remaining in the portfolio are the more challenging prospects. "Treasury is continuing to implement the three-pronged exit strategy" for Tarp, a Treasury spokesman said. "That strategy includes waiting for those banks that are able to repay in full in the near future to do so, restructuring the investments in limited cases, and selling investments through auctions in cases where the bank is not expected to pay in the future."