Sometimes it is good to see presidential approval over the very long haul– like since the birth of polling! Here are all Gallup presidential approval polls since Franklin Roosevelt, thanks to the Roper Center for the long term data and FiveThirtyEight.com for recent polls.
Gallup doesn’t do nearly as many approval polls now as they did in the past, so not many Biden polls. But the recent decline in approval is notable in comparison with past presidents. Yes, you need to zoom in.
Here are all polls of Biden approval, with my fit to the trend. See your favorate aggregation site for alternative averages. The gradual decline through July sharply accelerated in August. Not that this is news. However the decline in August continued at about the same rate in September, so no sign yet of flattening out.