The last president to have circulating dollar coins, then, will be James Garfield, whose coin was released last month. There are 18 more presidents scheduled for the series, with the next four presidents slated for 2012 -- Arthur, Cleveland, Benjamin Harrison and McKinley.
The coins are victim the longstanding popular resistance to using dollar coins instead of the iconic dollar bill. The Federal Reserve estimates that it has roughly 1.4 billion presidential coins in storage, since demand for them has been been so meager.
There's an upside for collectors, however. The dollar coins from Washington to Garfield aren't particularly valuable, since there are so many of them. A steep drop in mintage will likely make the rest of the series more valuable in the long run.