Since the inception of the Presidential Dollar Coin program, the U.S. Mint has unintentionally left off the missing edge lettering on several presidential dollars. The first year the Washington Missing Edge Lettering Dollars proved to be very popular. However, as time passed many examples with no edge lettering appeared in the market making prices decrease drastically. In 2008 the Mint also left off the edge lettering on John Quincy Adams Dollars. These proved to be much scarcer than the 2007 Washington Missing Edge Dollars and also scarcer than several other Missing Edge Lettering Dollars in the series. Therefore, prices also seem to be significantly higher.