• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
Finance

The stock market’s ‘presidential predictor’ just started signaling that Joe Biden will win the election

By
Jen Wieczner
Jen Wieczner
Down Arrow Button Icon
By
Jen Wieczner
Jen Wieczner
Down Arrow Button Icon
October 28, 2020, 5:52 PM ET

Our mission to help you navigate the new normal is fueled by subscribers. To enjoy unlimited access to our journalism, subscribe today.

For market watchers, this week’s stock rout—in which the S&P 500 has fallen 5.6% in three days—comes with additional significance: It could determine whether Donald Trump or Joe Biden will win the election.

For almost a century, the so-called Presidential Predictor, as dubbed by Sam Stovall—a well-known S&P analyst and the chief investment strategist for CFRA—has correctly determined the presidential election winner with only one exception, an 88% success rate.

It works like this: If the S&P 500 rises from August through October, the incumbent party (in this case, Republican—Trump) is reelected to the White House. If the S&P 500 falls over the three-month stretch, the Oval Office flips to the opposing party (in this case, Democrat—Joe Biden).

This year, for much of that period, stocks have soared to new highs, predicting a Trump reelection; as recently as mid-October, the S&P 500 Predictor was up 7.5%.

But that changed Wednesday as stocks plunged further. Now the S&P 500 is down over the critical time frame, albeit ever so slightly—by just 0.09 (such a small difference that the percentage change is basically flat), to 3,271.03.

That number will be the level to watch over the next couple of days: Because the Presidential Predictor counts the stock market’s performance only through October, Friday is the last day that matters for the indicator. Should the S&P 500 remain where it is or fall further over the rest of this week, the stock market predicts that Biden will become President.

“The next two days will be key!” Stovall noted in an email.

Stock market analysts believe the reason for the pattern is that investors dislike uncertainty: A change in control of the White House comes with uncertainty around new policies and legislation. The more likely that change becomes, the more uncertainty there is, which makes investors sell stocks.

Still, the metric isn’t perfect. In 1956, despite the S&P 500’s fall in the August-through-October period, Dwight D. Eisenhower won reelection to the presidency. The Presidential Predictor has not failed since then.

About the Author
By Jen Wieczner
See full bioRight Arrow Button Icon

Latest in Finance

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Leadership
  • Success
  • Tech
  • Asia
  • Europe
  • Environment
  • Fortune Crypto
  • Health
  • Retail
  • Lifestyle
  • Politics
  • Newsletters
  • Magazine
  • Features
  • Commentary
  • Mpw
  • CEO Initiative
  • Conferences
  • Personal Finance
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map

© 2025 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.


Latest in Finance

An NYSE trader looks at his computer monitor.
AIMarkets
‘Artificial stupidity’ made AI trading bots spontaneously form cartels when left unsupervised, Wharton study reveals
By Sasha RogelbergDecember 26, 2025
13 minutes ago
Intrator
AIBrainstorm AI
Outsiders see a circular economy. CoreWeave’s CEO sees a ‘violent change’ rattling the supply chain down to the inside of the earth
By Nick LichtenbergDecember 26, 2025
2 hours ago
Trump stands in front of a podium, about to speak
RetailHolidays
Trump just declared December 26th a national holiday. What’s open and closed?
By Dave SmithDecember 26, 2025
4 hours ago
CryptoWeb3
The world’s leading blockchain-based taxi app is setting its sights on New York City
By Angelica AngDecember 25, 2025
12 hours ago
InvestingCollectibles
Logan Paul auctions off $5.3 million Pokémon card, urging young people to invest more in nontraditional assets: ‘Don’t be afraid to take a risk’
By Sydney LakeDecember 25, 2025
22 hours ago
Mark Zuckerberg stands in a doorway
Real EstateMark Zuckerberg
Mark Zuckerberg gifted noise-canceling headphones to his Palo Alto neighbors because of the nonstop construction around his 11 homes
By Dave SmithDecember 25, 2025
1 day ago

Most Popular

placeholder alt text
Real Estate
Mark Zuckerberg gifted noise-canceling headphones to his Palo Alto neighbors because of the nonstop construction around his 11 homes
By Dave SmithDecember 25, 2025
1 day ago
placeholder alt text
Retail
Trump just declared December 26th a national holiday. What's open and closed?
By Dave SmithDecember 26, 2025
4 hours ago
placeholder alt text
Personal Finance
Trump turns government into giant debt collector with threat to garnish wages on millions of Americans in default on student loans
By Annie Ma and The Associated PressDecember 24, 2025
2 days ago
placeholder alt text
Economy
Even if the Supreme Court rules Trump's global tariffs are illegal, refunds are unlikely because that would be 'very complicated,' Hassett says
By Jason MaDecember 21, 2025
5 days ago
placeholder alt text
Retail
Trump just declared Christmas Eve a national holiday. Here’s what’s open and closed
By Dave SmithDecember 24, 2025
2 days ago
placeholder alt text
Success
Chinese billionaire who has fathered more than 100 children hopes to have dozens of U.S.-born boys to one day take over his business
By Emma BurleighDecember 25, 2025
1 day ago