in addition to the 1+ billion already in vaults, the mint must continue to make them. They are a series required by Act of Congress that honors Presidents. The bill, passed in 2005. requires a new coin be introduced every 3 months until all Presidents are covered. Production started in 2007 and they are presently up to Ulysses S. Grant, our 18th President. Unless Congress acts to stop this coinage, the production will continue until 2016.
It gets even juicier - so that nobody got their nose out of joint the law was written so that 20% of all $1 coins produced must continue to carry the likeness of Sacajawea. So.....for every 4 of the President coins (that no one wants) they have to produce a Sac dollar (that no one wants).
Final little goody. Who had this great idea? The guy who sponsored the bill had an (R) after his name. So did those who moved it through congress. Oddly enough, none of them involved seem to want to talk about it much these days. Plenty of boondoggle blame to go around!