Dollar Depreciation and the Unspoken Threat to U.S. Stock Market Returns

While market commentators often celebrate dollar weakness as a catalyst for global recovery and commodity strength, the historical record paints a more sobering picture. When the dollar loses value, U.S. stocks tend to become the underperformers—not the outperformers. This counterintuitive relationship, rooted in decades of market data, suggests that investors holding American equities may face years of disappointing returns ahead.

The 1971 Turning Point: A Case Study in Dollar Decline

The collapse of the Bretton Woods system in 1971 marked the first major test of what happens when the dollar plummets on the world stage. Over the following six years, the S&P 500 managed only a 5% total gain, translating to a meager 0.8% annual return—barely sufficient to keep pace with inflation. Meanwhile, investors holding German and Japanese equities witnessed entirely different outcomes. The DAX surged 160%, and the Nikkei 225 climbed an extraordinary 450% when converted back to dollars. This wasn’t luck; it was a structural reality of currency depreciation: when measured in a weakening currency, foreign assets become exponentially more valuable to international investors.

The Plaza Accord Pattern Repeats (1985)

Fourteen years later, history demonstrated it wasn’t a one-time anomaly. Following the Plaza Accord of 1985, the dollar weakened significantly, and U.S. stocks posted a respectable 54% gain over five years. But again, the global picture told a different story. German equities rallied 80%, and Japanese stocks soared 130%. Many observers at the time believed these overseas markets were “being harvested” by stronger forces, yet they dramatically outpaced American returns. The consistency of this pattern across two distinct historical periods suggests something fundamental about currency dynamics and equity valuation.

Today’s Risk: The $20 Trillion Question

The stakes have never been higher. Foreign investors currently hold approximately $20 trillion worth of U.S. stock positions. If the dollar continues its downward trajectory—as many bull market narratives suggest—we must confront a critical question: where will these capital flows move? When the U.S. currency loses value, foreign shareholders face a dual erosion of returns: stagnant stock prices coupled with currency losses. History indicates they will eventually seek better opportunities elsewhere, leaving American stock holders with the residual holdings.

The optimistic narrative about dollar weakness and bull markets ignores this historical reality. Rather than assuming the dollar’s depreciation will fuel gains in American equities, prudent investors should recognize the warning signs: they may be accumulating assets that could underperform significantly over the coming years. The lesson from 1971 and 1985 is clear—when the dollar falls, the global equity rebalancing that follows rarely favors U.S. stocks.