President Donald Trump. AP Donald Trump has already set a record for being the most unpopular new president since the invention of telephone polling. But I don't think job approval is the poll number Trump should be most worried about.

If I were him, I'd be worrying about the question the Quinnipiac University poll was asking about my leadership skills.

In a new Quinnipiac survey, out on Wednesday, only 42% of voters said they think Trump is a good leader, and 55% said he's not.

Trump's big thing is supposed to be leadership — he's the business guy, he hires the best people, and he knows how to shake things up in Washington and make America great again. Right?

In November, shortly after the election, 56% of respondents told Quinnipiac they thought Trump was a good leader, and only 38% said he wasn't. That's not too shabby for a guy who didn't even get the most votes.

But as Trump started actually doing stuff — running a transition, hiring people, issuing half-baked executive orders, firing his national security adviser after less than a month — the share of Americans willing to call him a good leader has steadily declined.

From 56% in November, it went to 49% in January, 47% earlier this month — and now 42%, or about 4 points less than his share of the popular vote.

In polling, you often analyze a question by measuring the difference between the share of respondents that gives the positive answer and the share that gives the negative one. By this measure, Trump was at plus-18 on the "good leader" question in November, and now he's at minus-13, a decline of 31 points in three months.

His term lasts another 47 months.

(Quinnipiac surveyed 1,323 adults in English or Spanish from February 16 to 21, with a margin of error of plus or minus 2.7 percentage points.)

An earlier version of this post incorrectly said Trump had 51 months left in his term. We regret the error.