U.S. economy: The stock market would need to fall this much to wipe out all of Trump's gains

Live by the Dow, die by the Dow.

The stock market, and the major indexes, aren’t the same as the economy. But they are indicators, especially for people who, at this point, break into a cold sweat whenever they check their 401(k) balance.

Donald Trump has frequently has played this up, claiming credit for hotly performing markets. Just a few samples from his Twitter account:

Dec. 23, 2017, “The Stock Market is setting record after record and unemployment is at a 17 year low. So many things accomplished by the Trump Administration, perhaps more than any other President in first year.”

Jun. 15, 2019: “The Trump Economy is setting records, and has a long way up to go….However, if anyone but me takes over in 2020 (I know the competition very well), there will be a Market Crash the likes of which has not been seen before!”

Then, on Jan. 9, 2020, Trump wrote, “STOCK MARKET AT ALL-TIME HIGH! HOW ARE YOUR 401K’S DOING? 70%, 80%, 90% up? Only 50% up! What are you doing wrong?”

That was then.

If someone claims the credit for markets, ultimately they’re saddled with the blame if things go badly. Which they have. Tuesday’s strong gains still don’t make up for Monday’s panicked tumble or all the previous retreat.

The recent drops in fact put the gains notched under Trump’s first term far below the gains in the market under Obama’s first term.

The question now is how long can Trump, looking for reelection, expect the market to hold whatever gains it made during his administration. The Russell 2000—the index of small- and medium-cap companies—is already back to where it was when Obama left office. The table below shows how much of the gains the other indexes still have.

James Carville’s famous three-word election mantra—it’s “the economy, stupid”—is more than a campaign war story. A presidential election is “deeply connected to the economy,” said Nicholas Goedert, an assistant professor of political science at Virginia Tech.

That’s especially true in the last nine months before the election, according to Goedert. He said multiple studies have shown that the economy in the first two years of a president’s term don’t appear to matter nearly as much. The third, barely. As to Ronald Reagan’s famous question, “Are you better off than four years ago?”, people apparently don’t remember that far back. All they want to know is what a president has done for them lately.

If stock markets are the measure, as Trump has repeatedly said, the answer might be, “Not much.”

But will the losses continue or reverse and again give Trump material to tout? Some financial experts think an ongoing fall is unlikely. “This has been a panicked sell-off,” said Ivan Feinseth, research director and chief investment officer at Tigress Financial Partners. “The market’s gone higher from every major sell-off. It may slow things for a quarter or so, maybe.”

“At some point, selling will be exhausted,” meaning that after intense panic selling, eventually shares hit a natural price bottom and start to rebound, agreed Quincy Krosby, chief market strategist at Prudential Financial.

And yet, a turnaround might take longer to achieve. “The problem is we’re coming off record highs and an over-valued market is nobody’s friend,” said James Angel, a professor of finance at Georgetown University. By a variety of traditional measures of share values, Angel says “the market is very, shall we say, optimistically priced.”

Nancy Davis, chief investment officer of Quadratic Capital, thinks losses could continue so long as U.S. bond interest rates (called yield) remain at historical lows. She said that the 10-year bond in particular, is now trading low enough to suggest a coming recession. “Now we’re in full-borne crazy territory,” Davis said.

To understand how long in theory indexes might have to lose their Trump gains, Fortune analyzed the S&P 500, Dow, and Nasdaq, marked their 2020 highs, and calculated how much, on average, they lost per trading day—even accounting for the periodic big jumps that have been part of the roller coaster ride during the last few weeks—to reach their values on Tuesday’s close.

There is no way to predict the future in markets. But if the overall pace of the last few weeks did continue, the S&P 500 would be back at Trump’s inauguration in 17 trading days, the Dow Jones in 21, and Nasdaq in 27.

In other words, in just over a month, investors could be ready to party like it’s 2017.

How much the stock market would need to fall to wipe out all of Trump’s gains

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