So most of 2017 was spent celebrating a number that just kept going up and up: The stock market. The Dow was soaring, and Trump was tweeting and all was well. Each day the market was up was a good day for Trump and he missed few opportunities to make that case to the public.
And then it wasn't.
At the weekend NZT, the Dow fell 666 points, the sixth-worst plunge in its history. The Standard & Poor's 500 fell about 60 points, a smaller drop as a function of its value, but still a bad day for the index. Trump, true to form, was mum about the drop.
Today, an even sharper fall. The Dow closed down 1178 points, the biggest single-day fall in the average's history. The S&P dropped about 113 points - its largest drop, too. The Dow closed 8.5 per cent off its all-time high and the S&P off 7.8 per cent. The two-day fall was the worst in Dow history and the fourth-worst in the S&P's.
More frustrating for Trump? The Dow has now given up a third of the gains it has seen since he was inaugurated and more than a quarter of the gains it has seen since the election. The S&P's drop was more severe, losing 37 per cent since inauguration and 31 per cent since November 8, 2016. Both are still up since Trump took office, but the recent trend does stand out.
By February 5, 2010, the Dow had gained 26 per cent under Barack Obama. Trump was on track to beat that easily - until the past two days of trading.
Everyone saw this coming. Stock markets don't go up forever. Markets often go down, occasionally spectacularly. Trump's constant insistence on the strength of the markets being a positive reflection of his presidency meant that, inevitably, it would be noted when the markets dropped significantly. His political opponents were easily teed up. A no-brainer.
Former Obama press secretary Jay Carney tweeted:
"Good time to recall that in the previous administration, we NEVER boasted about the stock market - even though the Dow more than doubled on Obama's watch - because we knew two things: 1) the stock market is not the economy; and 2) if you claim the rise, you own the fall."
It's worth remembering the broader context here. The Dow's biggest single-day fall comes when it was near its highest value - meaning that, as a percentage of the average, the fall wasn't the largest. It's the second-biggest drop as a percentage of value since 2009 and the 102nd biggest in history. There have been 192 days on which the S&P has seen bigger single-digit falls in the percentage of its price. Even over the past two days, the declines as a percentage of market value are more modest. For the Dow to have seen a record fall in per cent of market value, it would have needed to fall more than 5770 points. So: Could have been worse.
From a political perspective, Carney's right. The Dow, like an approval poll, is a very iffy thing to celebrate each time it goes up. It's very Trump to champion short-term increases in the market, sure, and very Obama to stoically nod at long-term increases in private. But just because those responses are in character doesn't mean that Obama's strategy was not better.
It was better.
With the notable exception that Trump operates by different personal and political rules.
Constant reversals of even some of his most fervently asserted positions have elicited little more than shrugs from many of his supporters and don't seem to have fazed him much, either.
Supporters will note - correctly - that the markets are still up during his presidency and many will take from that the lesson that Trump intended all along: That he is an exceptional manager of the American economy.
The Dow isn't the economy, and Trump's ability to move either of those things at his will is certainly debatable. But if you are inclined to think that things Trump does are great, you will probably still think that Trump's handling of the economy is great no matter what the Dow does.
Trump, for one, is so inclined.
