The S&P 500 Is Not the Sure Bet Many Investors Think

For many investors who started saving in the last 15 years, the S&P 500 has looked like a machine that only runs one way. Buy the index, hold it, and the account tends to grow. That experience has hardened into a belief that stocks always go up eventually. The longer history tells a more complicated story.

The index has, at times, delivered very little to its owners over long periods. The S&P 500 peaked in March 2000 and did not regain that level until 2013, more than a decade in which a buyer at the top saw no price gains. Investors who bought near the 1929 peak waited roughly 25 years to get back to that level in nominal price terms. Dividends make the full return picture better than price alone, but the price-only path is what many people see when they check their balance.

Why does this matter? Long-run returns depend heavily on the valuation you pay at the start. When stocks are expensive relative to company earnings, the years that follow have historically offered lower average returns. Inflation also erodes gains in real terms. An investor who holds through a flat decade can still come out fine, but mainly if they can afford to wait and keep investing through the slump.

None of this means indexing is a mistake. Broad diversification remains one of the most widely recommended approaches for ordinary savers. The point is that "stocks always go up" describes very long horizons, not a promise about the next five or ten years. Anyone who will need the money sooner should think about how a sideways market would affect their plans, and should be cautious about treating the most recent bull run as the normal state of affairs.