KEY TAKEAWAYS
After a calm start to the year, stocks took a downward turn late in the first quarter as investors around the world weighed the impact of geopolitical events, notably the war in Iran. In the US, the S&P 500 was down for 2026 as of March 20 after hitting record levels earlier in the year.1 Equity returns in developed international and emerging markets were better than in the US, despite the instability in the Middle East. In the bond market, US Treasuries were lower, with the benchmark 10-year yield rising to nearly 4.4%.2

Through March 20, the S&P 500 Index fell 4.7% and the tech-heavy Nasdaq lost 6.7%. Technology companies pulled back from recent highs amid ongoing concerns about the impact of AI on certain industries, with software stocks in particular declining.3 Trade developments also remained in focus as the US Supreme Court said certain tariffs imposed by the administration using emergency powers weren’t legal.4 Market reaction to that ruling was largely muted, perhaps reflecting expectations already priced in about which way the court would rule.
Market volatility rose and oil prices spiked after the US and Israel struck Iran in late February, with hostilities continuing in Iran and elsewhere in the Mideast into March. The impact on crude supplies helped push oil prices notably higher.5 Amid growing concerns about energy, it is worth remembering that global equity returns have not been correlated with the level of oil prices (see Exhibit 1). While the cost of oil may have some impact on markets, it is just one of many factors that investors consider when looking at market performance.
Exhibit 1: Stocks and Barrels Annual returns for MSCI World Index (net div.) vs. end-of-year crude oil spot prices, 1970-2025

Global equities, as measured by the MSCI All Country World Index (net dividends), fell 3.1% as of March 20. Stocks in developed international markets outside the US fared better, losing just 1.5%, as measured by the MSCI World ex USA Index (net dividends). The MSCI Emerging Markets Index (net dividends) fared even better, gaining 4.5%.6 Global equity markets remain near long-term highs, even in the face of geopolitical challenges; over the past few years, stock markets have had positive returns despite numerous conflicts around the world.
Along with the fear and hardship always associated with armed conflict, there can be concern for investors over potential impact on investment performance. But it’s important for investors to be cautious about making asset-allocation changes in response to such events. Markets are forward-looking, and prices move in response to changes in information. When unexpected developments arise that investors deem to be poor for markets, markets often drop. But the flip side is markets always set prices for positive expected returns. Once the news gets reflected in market prices, investors can still expect positive returns even amid worrisome circumstances.
The US Federal Reserve held the federal-funds rate steady in a range between 3.5% an 3.75% at meetings in January and March.7 Fed members continued to disagree over which posed the bigger threat—persistent inflation that might argue for higher rates, or a sluggish labor market that may call for lower ones. In February, the US core consumer price index, which excludes more-volatile food and energy items, rose 2.5% from a yearago, slightly above the Fed’s target rate of 2%.8
During the first quarter through March 20, US Treasuries were 0.6% lower, sending the yield on the benchmark 10-year Treasury up to 4.39%.9 The broader bond market also declined, with the Bloomberg US Aggregate Bond Index down 0.7% and the Bloomberg Global Aggregate Bond Index (hedged to USD), a broad benchmark of sovereign and corporate debt, falling 0.5% as of March 20.10
Foot Notes:
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RISKS
Investments involve risks. The investment return and principal value of an investment may fluctuate so that an investor’s shares, when redeemed, may be worth more or less than their original value. Past performance is not a guarantee of future results. There is no guarantee strategies will be success