[ordinary]

This seems to be happening with many presidents in their first 200 days. See Johnson, Eisenhower, Kennedy and Bush Sr. for examples. Also check out Nixon, who manages to go up on both metrics for the first 200 days.

The numbers support this: on average, 32% of the population is neutral towards a newly elected president. After 200 days, this has gone down to 19%. The same numbers for approval ratings remain steady: from 64% to 63%, while those for disapproval necessarily go up: from 4% to 18%.

This means that even the people who voted against the winning candidate (always between 40% and 60% of the turnout[0]) are initially mostly neutral towards them. But while the people who voted for him stay loyal for a bit (possible because they don't want to feel they've been deceived), the people who voted against him have no qualms about voicing their disapproval.

I have to admit that this "let's wait and see" attitude was pretty surprising to me. It seems like people refrain from judging a president until after he has actually made policy, as opposed to immediately upon taking office, as I would have expected them to do.