Strange but true: From 1840 through 1960, every president elected in a year ending in zero died while in office.
Some called it "The Curse of Tecumseh," after the Shawnee chieftain who was killed by the forces of General William Henry Harrison in 1813. Tecumseh's brother, Tenskwatawa, supposedly prophesied bitterly that Harrison would die if he were elected president. (In truth, there's no proof that Tenskwatawa ever said any such thing.) Harrison was elected in 1840, died after barely a month in office, and the "curse" was off and running.
140 long years later, Ronald Reagan finally broke the string by serving two full terms as president before stepping down in 1989 -- though he had to survive a 1981 assassination attempt to do so. George W. Bush was elected in 2000 and also served two full terms. The killer Curse of Tecumseh turned out to be the Coincidence of Tecumseh after all.
Still, it was quite a deadly run. Here's the full roll call of 0-year presidents in American history.