‘We Will Get Into a Lost Decade Again. That’s Almost a Guarantee,’ Says Top Portfolio Strategist

Lance Roberts, Chief Investment Strategist at RIA Advisors, believes investors are underestimating a risk that has surfaced more than once throughout market history. Speaking on a recent episode of Thoughtful Money with host Adam Taggart, Roberts issued a stark warning: “We will get into a lost decade again. That’s almost a guarantee.”

Roberts is not predicting an imminent crash. The S&P 500 has gained more than 28% over the past year, and the CBOE Volatility Index (VIX) sits near levels that typically signal investor confidence and market calm. His concern runs deeper: today’s strong returns may be pulling future returns forward, setting up conditions that could produce years of disappointing performance down the road.

What a Lost Decade Actually Looks Like

A lost decade does not require markets to collapse. It simply means investors spend years earning little or no real return after inflation, often amid periods of sharp volatility that test conviction at exactly the wrong moments.

The clearest modern example ran from 2000 to 2010. Using the SPDR S&P 500 ETF Trust (NYSEARCA:SPY) as a proxy for the index, the fund moved from $145.44 on January 3, 2000, to $125.75 on December 31, 2010, a price change of -13.54% before dividends over the full ten years. That decade included two roughly 50% drawdowns, the dot-com crash and the financial crisis, and tested the patience of every buy-and-hold investor who lived through both.

Today’s surface conditions look very different. Corporate profits remain at historically elevated levels. According to the Bureau of Economic Analysis third estimate (released June 25, 2026), U.S. corporate profits reached approximately $4.43 trillion on an annualized basis in the first quarter of 2026. On a total-return basis, SPY has gained roughly 314% over the past ten years and approximately 86% over the past five, with another 10% added year to date through mid-August 2026.

Why Roberts Thinks Returns Could Slow

Roberts’ thesis rests on three familiar pillars. The first is valuation. Stocks are trading at elevated levels relative to most historical benchmarks. Goldman Sachs noted in its 2026 Investment Outlook that “valuations are high in both public and private markets.” More recently, in May 2026, Goldman raised its year-end S&P 500 price target to 8,000 while acknowledging that the index trades at roughly 21 times forward earnings, above the ten-year historical average of around 19x. Earnings growth has so far supported those multiples, but the cushion is thin.

The second pillar is concentration. A small number of mega-cap technology companies have driven an outsized share of recent market gains. If leadership narrows further or earnings growth among those names disappoints, the broader market becomes more vulnerable than headline index returns suggest.

The third is straightforward mean reversion. Periods of unusually strong returns have historically been followed by extended stretches of weaker ones, and the mathematical relationship between starting valuations and subsequent decade-long returns is one of the more reliable patterns in long-run market data.

The interest-rate environment sharpens the picture. The 10-year Treasury yield has climbed to approximately 4.69% as of August 17, 2026, near its highest level in 19 months, and up meaningfully from the 4.45% level cited when Roberts first made his case. That yield gives investors a credible risk-free alternative that simply did not exist during the ultra-low-rate era, raising the hurdle stocks must clear to justify their current multiples.

Taggart’s Tough-Love Pivot

Host Adam Taggart expanded on Roberts’ warning by redirecting the conversation toward personal responsibility. “You have two choices, which is one, I can blame others for my situation, or I can take responsibility for my situation,” Taggart said. “Has anything ever gotten better in your life by blaming others for your situation?”

He also drew on the lesson many investors absorbed during the 2008 financial crisis. “People that got devastated during the financial crisis weren’t prepared for it to start with. People that survived it were financially prepared for it to start with.” His broader point was that a sound financial plan builds enough flexibility to absorb prolonged drawdowns before they happen, not in response to them.

What to Watch Next

Roberts is urging investors to assess their portfolio risk, diversification, and cash positioning now, while markets remain strong, rather than waiting for conditions to deteriorate. Whether a genuine lost decade materializes depends on factors no one can predict with certainty. What investors can control is how prepared they are if it does.

Editor’s note: This article has been updated to reflect the BEA’s third-estimate figure for U.S. corporate profits in Q1 2026 ($4.43 trillion, revised from $4.39 trillion), the current 10-year Treasury yield of approximately 4.69% (up from 4.45%), updated SPY total-return figures through mid-August 2026, and Goldman Sachs’s May 2026 S&P 500 target revision to 8,000 alongside the firm’s current forward P/E estimate of roughly 21x.

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