Oil Shock Reshapes Market Forecasts

When the Iran conflict sent oil prices to roughly $100 per barrel, the major investment firms that manage trillions in retirement assets moved fast. Vanguard's Investment Strategy Group updated its 10-year Capital Markets Model forecasts as of March 31, 2026, explicitly incorporating the new Middle East reality. Their language is direct: the conflict has created a stagflationary shock — rising inflation AND slowing growth at the same time — forcing central banks to choose between fighting inflation and propping up a weakening economy.

Fidelity's April 2026 market outlook flags that oil futures markets are signaling continued supply tightness in the near term, with the Strait of Hormuz — the chokepoint for a significant chunk of the world's oil supply — remaining a pressure point.

The Numbers From the Firms That Manage Your Retirement

Schwab — as of January 2, 2026, the firm published its 2026 Long-Term Capital Market Expectations. Their forecast for U.S. large-cap equities: 5.9% annualized over the next decade. That's down from their prior estimate of 6%. The reason? Market prices outpaced earnings growth.

Research Affiliates — CIO Que Nguyen projects just over 3% annualized returns for the S&P 500 over the next 10 years, citing valuation stretch and extreme market concentration in a handful of mega-cap names.

Vanguard — updated their model as of March 31, 2026. Their new forecasts factor in revised assumptions for growth, inflation, and monetary policy, with the Iran conflict incorporated into the projections.

For context: the long-run historical return on U.S. stocks since 1926 has been 10.1% per year, according to Hendrik Bessembinder, a professor at Arizona State University's Carey School of Business. A decade of 3-6% returns represents a generational downshift.

The Iran Conflict and Market Performance

Fidelity's director of global macro research, Jurrien Timmer, noted that "The cyclical bull market, now 45 months strong, has been bent but not broken." The S&P 500's maximum drawdown from the Iran conflict so far has been less than 10%. As of April 14, the index was up nearly 2% year-to-date, sitting just 1% below its all-time high set January 27.

Historically, oil shocks trigger recessions and bear markets. The reason that hasn't happened yet is that corporate earnings are still growing fast — the forward earnings estimate has been expanding at a 17% annual rate, according to Fidelity. Profit margins for S&P 500 companies hit roughly 15% in early April.

But earnings momentum is a lagging signal. Companies don't feel the full squeeze of $100 oil in the same quarter it hits. Supply chains, consumer spending, and capital costs all take time to transmit the shock. Fidelity is optimistic. Vanguard is more cautious. Both firms are weighing the risks differently.

What Financial Media Is Missing

Financial media keeps running the headline that markets are "resilient." The framing serves a purpose — it keeps retail investors calm and assets under management stable — but it obscures the real question. "Resilient" means stocks haven't crashed yet. It says nothing about whether you'll earn real returns over the next decade.

Schwab is explicit about the problem: elevated valuations, market concentration, tight credit spreads, and a flatter yield curve all "complicate the current investment landscape." The setup was difficult before Iran made it worse.

Research Affiliates' Que Nguyen isn't hedging. Three percent annualized barely beats expected inflation. For a 55-year-old with retirement concentrated in an S&P 500 index fund, that projection presents a genuine challenge.

The AI Valuation Question

Fidelity raised a fair point: six months ago, the biggest fear was an AI bubble. That bubble has not popped. Timmer notes that compared to the unchecked enthusiasm of 2000, investors have been more skeptical of AI valuations, which has prevented the kind of vertical blowoff that preceded the dotcom collapse.

Schwab noted that during the first half of 2025, the "Magnificent 7" pulled back, international equities outperformed U.S. stocks, and the dollar weakened. U.S. markets recovered in the second half. The lesson: diversification matters, and conditions change fast.

What This Means for Regular People

If you're 30 with 35 years until retirement, stay invested and stop checking your account every day. Sam Stovall, chief investment strategist at CFRA, says it plainly: over long periods, "you should be in stocks, period, if you want to outpace inflation and taxes."

If you're 55 or older with a heavy S&P 500 concentration, three firms just published specific numbers showing the next decade looks nothing like the last one. The Iran conflict didn't create that problem. It inherited it and added fuel.

Vanguard is modeling a stagflation scenario — the worst-case combination where your investments underperform AND your cost of living rises. Central banks can't fix both at once. Plan accordingly.