From The Hill, “Gallup will no longer measure presidential approval after 88 years”:
Gallup will no longer track presidential approval ratings after more than eight decades doing so, the public opinion polling agency confirmed to The Hill on Wednesday.
The Hill
Mentioned a few graphs down:
President Trump has seen his rating by the agency slip in recent months, peaking at 47 percent last February and dipping to less than 37 percent in its last poll taken in December.
I’m sure that’s just a coincidence.