The S&P 500 is on the verge of joining one of the most exclusive streaks in market history.

The benchmark index – tracked by the SPDR S&P 500 ETF Trust (SPY) – secured its ninth consecutive daily gain on Tuesday, after closing at 7,612 points.

While nine-day winning streaks are uncommon, another positive close on Wednesday would elevate the move into far rarer territory: a 10-session winning streak, something seen only eight times since 1970.

And history suggests that while such momentum often reflects powerful bullish sentiment, investors shouldn't automatically assume more gains lie ahead.

S&P 500 Eyes Rarest Winning Streak Since 1995

For the S&P 500, a nine-day run is the 17th of its kind since 1970. The most recent occurred in May 2025, when stocks surged as investors unwound tariff-related fears.

Excluding last year's episode, the most recent occurrences came in November 2004, June 1997, September 1995 and January 1992.

Stretch it to 10 sessions and the company gets far more exclusive: only eight times in 55 years has the S&P 500 closed higher for 10 straight days, and the most recent was September 1995.

What Happens After a 10-Day Winning Streak?

History offers a surprisingly mixed verdict.

Forward-return analysis shows that the S&P 500's performance following a 10-session winning streak has generally lagged normal market returns.

One month after the signal, the index produced an average gain of just 0.5%, compared with an unconditional average return of roughly 0.8%.

Three-month returns averaged 1.8%, also below the historical norm of 2.2%.

The six-month picture is even weaker. Average returns turned slightly negative at -0.7%, versus a typical gain of 4.5%.

The 12-month outlook improved somewhat, with an average gain of 2.1%, but that still trailed the S&P 500's long-term average annual return of about 9%.

The median tells a calmer story. The middle 12-month outcome, less distorted by extremes, was a healthier 7.12%, and the win rate remained above 50% across all horizons, reaching 75% one month out.

Is This 1995 Or 1989?

The most interesting comparison may not be the averages but the enormous divergence between individual historical outcomes.

Two episodes stand out.

In September 1995, the S&P 500 completed a 10-session winning streak and continued climbing as the technology boom gathered momentum.

What followed became one of the strongest bull-market phases in modern history.

Twelve months later, the index had gained more than 16%, significantly outperforming a typical year for stocks.

The rally ultimately evolved into the late-1990s internet-driven surge that culminated in the dot-com bubble.

The October 1989 episode tells the opposite story.

Fresh off a historic winning streak, the S&P 500 initially appeared unstoppable.

Yet one month later the index had fallen more than 6%, and losses continued to mount over the following year. Twelve months after the signal, the market was down roughly 15%.

The Bigger Picture

The current rally arrives amid one of the strongest AI-driven market advances on record.

Semiconductor stocks have surged, corporate earnings expectations continue to rise, and investors remain willing to pay increasingly higher valuations for companies exposed to artificial intelligence infrastructure.

That backdrop arguably makes the current environment look more like 1995 than 1989.

Still, history suggests that once the S&P 500 reaches the extremely rare milestone of 10 consecutive gains, future returns tend to become less predictable and often less rewarding than investors expect.

Momentum can persist, but the historical record shows that after such extraordinary streaks, the easy money has usually already been made.

Image via Matej Kastelic/Shutterstock