I recently ran into a graph on 538's site about former president's approval ratings and I became quite interested in events that contributed a significant change in public perception of various former US presidents.

-Ford going from 71% to 49% in one day [day 31]. This seems to be when he pardoned Nixon.

-Truman started with an incredibly high approval rating. Which seems like it should be attributed to America's success in WW2 & Germany's surrender to Truman a few weeks into his presidency.

-Bush soared in popularity around 238~ days into his presidency, which corresponds to an attack.

Would anyone care to expand on the following gains and drops:

What occurred around 130 days into Bill Clinton's presidency to make him so unpopular?

What happened after Regan's first 140 days that led to him being so unpopular at the time?

What occurred towards the end of Eisenhower's first year in office [day 242] and how did he rebound around day 331?

Bush senior, at 350 days?

Carter, at 236 days?

Truman, day 275 and at day 329?

Nixon's approval ratings never became so low as Ford's. Did Nixon leave office before the public turned against him? Was Watergate considered more acceptable to the public back then? Why did people hate Ford more than Nixon?