Determining a presidency's success by inspecting its "first hundred days" is a bit of an artificial construct.
If humans were born with 12 fingers, then perhaps we'd be evaluating presidents based on their first 144 days instead.
If the Earth rotated a bit more slowly, then presidents would have more time to notch accomplishments.
Then again, 100 days is plenty of time to get a rough handle on the shape and thrust of a presidency - and to evaluate what kind of progress a leader has made toward fulfilling campaign promises.
The first 100 days of Donald Trump's presidency have been anything but boring or slow, but how much of it was sound and fury and how much entailed real action?
Here's a quick review of some of the peaks and valleys.
The wall
Let's start with the wall - not the president's only promise, but certainly one of his oldest, most high-profile ones. Candidate Trump constantly spoke at his campaign rallies of the great wall that he planned to build along the US-Mexico border.
The crowds roared in agreement when he said Mexico would pay for the project.
Contrast that certainty with this tweet, which Mr Trump himself wrote over the weekend.
Eventually, but at a later date so we can get started early, Mexico will be paying, in some form, for the badly needed border wall.
— Donald J. Trump (@realDonaldTrump) April 23, 2017
It's a case of Trump promises meeting political realities, in 140 characters or less. Campaign rhetoric is easy, turning talk into action in Washington is much more complicated.
The administration has pledged to reshuffle some money to begin wall construction, but it is increasingly clear that Congress will need to find billions of dollars to make the wall a reality.
That sets up a showdown between the president and legislators, with many Republicans - particularly those representing areas along the US-Mexico border - not keen on opening up the federal purse for Mr Trump's pet project.
Promise kept? Nope.
Supreme Court
Mr Trump promised to choose a Supreme Court justice to fill the empty seat on the bench from a list he released during the presidential campaign - and, by tapping Neil Gorsuch, he did.
"I've always heard that the most important thing that a president of the United States does is appoint people - hopefully great people like this appointment - to the United States Supreme Court," Mr Trump said at Mr Gorsuch's White House swearing-in ceremony.
"And I can say this is a great honour. And I got it done in the first 100 days. That's even nice. You think that's easy?"
That kind of depends how one defines "easy". Mr Gorsuch's confirmation hearing was bruising, no doubt. Facing united Democratic opposition, Republican Senate leader Mitch McConnell broke with longstanding precedent to allow a simple majority vote for Supreme Court confirmations.
Once that was done, however, it was simply a matter of the Republican majority in the Senate imposing its will.
While Mr Trump may have only had to put a name on a piece of paper and rely on Senate Republicans to do the heavy lifting, he did tick a major item of his presidential to-do list.
He satisfied a Republican base that stuck with him through a tumultuous campaign on the understanding that they'd get just such a reliable conservative on the court.
They may continue to stand by this president in the hope there will be more nominees like Mr Gorsuch to come.
Promise kept? Definitely.
Healthcare
"Nobody knew healthcare could be so complicated."
It's way too early for political epitaphs, but if the Trump presidency collapses under the weight of disorganisation and broken promises, this February quote from the president - made as it became increasingly clear his own party couldn't even agree on healthcare reform - will make a fitting inscription for a tombstone.
At one point during the presidential campaign, Mr Trump promised that the Democratic healthcare reform legislation - Obamacare, as it has become known - would be repealed on his first day in office.
Then, after the first Republican legislative effort crashed and burned in late March - 64 days into his presidency - Mr Trump backtracked on his timeline.
"I never said repeal it and replace it within 64 days," he said. "I have a long time. But I want to have a great healthcare bill and plan, and we will. It will happen. And it won't be in the very distant future."
Since then there's been speculation that a new deal could be in the works - but such rumours have evaporated upon closer scrutiny.
There's no telling what the future may bring, but the reality at this point is that healthcare reform was Mr Trump's first major legislative push - the de facto focus of his first 100 days in office - and it has done nothing but expose the Republican Party as fractured body incapable of advancing a coherent agenda.
Promise kept? Uh, no. Definitely not.
- BBC