Moment of numismatic geekery: The U.S. Mint's Presidential 2016 One Dollar Coin Proof Set is the last one, the only one to be a three-coin and not four-coin set, and the only one to feature presidents all of the same political party. There's no Jimmy Carter in the 2016 set. It's not a conspiracy. It's because Carter's not dead. Somehow, I suspect the legislation that created the presidential $1 commemorative coins series decided that the best name for the project wasn't "The Dead President Coins," but that's what it is, really; living former presidents aren't meant to be included, and the fact that all three in the 2016 set are Republicans is just an accident of history.