Because the economy was pretty good in 1978, and the media didn't lie about everything back then.
^^^^This.
11 million jobs were created during the Carter administration. Too bad that Iran decided to wait until Reagan's inauguration day to release the hostages. It's not too much of a conspiracy to think that there was some sort of deal there, similar to Nixon sabotaging the Vietnam peace talks right before the 1968 election. After all, there was the Iran-contra scandal later.