It is President Trump himself who has established that the Dow Jones industrial average should be considered a gauge of his success. He did so in a tweet last month, celebrating how well the market had performed since he was elected.

The day prior, his adviser Kellyanne Conway had made a similar point.

It prompted us to create a real-time tracker of how Trump was doing at his job, as measured in the daily fluctuations of nation’s premiere stock index. As of writing, incidentally, the Dow is down 0.29 percent, meaning, apparently, that the markets no longer “like the policies, action, and vision of @POTUS.”

Granted, press secretary Sean Spicer has insisted that single-day movement isn’t really the sort of thing that should be watched — something he said on a day when watching the Dow would have suggested that Trump wasn’t doing that great. It’s long-term trends, then, that are worth noting.

About that.

On Wednesday, Trump once again excoriated the “failing” New York Times on Twitter.

Mind you, the Times never apologized for its coverage and that coverage has demonstrably held up. But let’s focus on that word “failing.” The Times is failing, we can assume, in the sense that it’s failing as a business.

The only problem? The Times is actually doing better on Trump’s beloved stock-market metric than is the Dow.

That’s since the election. If we look just at the period since the inauguration — the period for which Trump had the reins of the American economy — it still holds true.

Since the election, the Times has done twice as well as the market overall. Since the inauguration, nearly that much. The markets continue to like the policies, reporting and strategy of @nytimes, I guess.

The problem for Trump here is obvious. If 29 percent growth since the election is failing, how do we describe the 13 percent growth that Trump’s so proud of?