U.S. Rep. Jim Jordan, Republican of Ohio, tweeted this analysis of the stock market Monday morning:
Jordan is implying that your 401(k) is not doing as well under President Biden as it did under President Trump. Under President Biden, the Dow Jones Industrial Average, an index of 30 prominent stocks, is up just under 10% through about 16 months, while under President Trump, the Dow increased more than 50% in four years. 
If the Dow continues performing this way for the rest of Biden’s term, your 401(k) account may not perform as well as it did under Trump, especially if it contains mostly stocks.
But this thinking ignores how investing actually works.
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1. Investing is cumulative
Comparing the stock market’s performance based on who is president makes for good Twitter fodder, but it’s not very useful information in real life. Your portfolio doesn’t reset when a new president takes office. The 10% gains under Biden may not compare well to the 50% increase under Trump, but the increases under Biden are *on top of* the performance under Trump. Your portfolio is still better off today than it was at any time under Trump.
2. Your 401(k) is a long-term investment
Your retirement funds don’t need to deliver over four-year horizons, as presidents do. Their performance matters on a much longer time scale. When you invest over the long-term, it helps to ignore the short- or even medium-term fluctuations of the markets and trust that over the decades before your retirement, the economy will grow steadily enough to fund your post-work years.
3. It’s not clear whether presidents influence the stock market
People invest retirement funds in the stock market because it generally goes up over the long-term. The only presidential administrations in the past century that saw negative stock market returns were George W. Bush, Jimmy Carter, Richard Nixon, and Herbert Hoover. Under 14 out of 18 presidents, your 401(k) would have done just fine.
There’s no rhyme or reason explaining why the stock market happened to do badly while those four men were presidents. Research shows stock market returns tend to improve under Democratic administrations, but with a sample of only 18 presidents over 100 years, it’s hard to draw the conclusion that Democrats have special stock-market-boosting powers.  If they did, they’d probably win more elections.
It’s doubtful Jordan, who has a history of missing important details, considered any of this when he tweeted. He probably just wanted to score some quick political points. (Jordan did not immediately respond to a request for comment.) And short-term sentiments like this can have an impact on investments, as researchers have shown based on the correlation between popular music and the stock market. But when you’re investing over the decades for your retirement, your portfolio is going to outlast any single president: you’re betting that the economy will grow bigger and stronger over the next two-to-four decades, not over the next four years.
“Instead of focusing on cheap shots politicians fire across the aisle,” says Ian Bloom, a certified financial planner and owner of Open World Financial Life Planning, “I would always have my clients look for the things they can control: ‘Am I allocated properly? Given how great the labor market is, am I getting the most for my skills? Am I saving what I should be toward retirement and other future goals?’ If those things are in alignment, we’ve done what we can for now.”
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