On Monday, as the market again reached a new record high, Trump tweeted that the first year of his presidency had seen 70 record closes (presumably he meant 70 record-high closes), which he said was more than any previous year. Wolfers, professor of economics and public policy at the University of Michigan and several other institutions, soon shot back saying the stock market performed better under Obama than under Trump at the same point in their presidency. Wolfers cited the S&P 500 instead of the Dow and looked at relative gains under each president rather than all-time nominal value.

70 Record Closes for the Dow so far this year! We have NEVER had 70 Dow Records in a one year period. Wow!

— Donald J. Trump (@realDonaldTrump) December 18, 2017

The market (the S&P 500) has risen 17.5% so far in the Trump presidency.
It rose 37.5% over the equivalent part of the Obama presidency. https://t.co/K4gETlbmcx

— Justin Wolfers (@JustinWolfers) December 18, 2017

Justin Wolfers is indeed correct on his S&P 500 numbers for the first 11 months of Obama’s and Trump’s respective presidencies based on a running percentage gain in the index over the course of the 11 months of Trump’s presidency so far.

Wolfers’s point about Obama and Trump stands even if you look at the percentage gains in the Dow under the six most recent presidents, though Trump either out-performs or slightly under-performs George HW Bush depending which index you use.

Ultimately, Clinton had far and away the best stock market results of the four most recent two-term presidents, followed by Obama, then Reagan, and, trailing far behind with negative gains, George W. Bush, whose presidency ended at the beginning of the Great Recession.

It’s not clear where Trump saw the claim that 2017 was the first year with 70 record-high closes, but Bespoke Investment Group, a Harrison, N.Y. investment firm, backs him up, reporting that 1995 had the second-most record-high closes, with 69, followed by 1925, with 65. Given that these other two banner years occurred during pre-recession bubbles, Trump may be well advised to downplay this particular achievement.

The larger point Wolfers seems to be making with his response to Trump is that looking at the number of record-high closes in a narrow period is not a particularly good indicator of economic performance—particularly for a president who inherited a stock market that was already relatively high in value. Moreover, many economists don’t put much stock in the Dow. It is not inflation-adjusted and is highly curated, measuring only the best performers in the economy.

It was a good year—just maybe not that good.