The bull market in stocks is about to enter its fifth year — here's what the data says is next

Break out the birthday balloons for the bull market .

Investors are currently living in the 11th bull market since the 1950s, which is on track to become the seventh to complete at least four full years on Oct. 12, according to a new analysis by Truist co-chief investment officer Keith Lerner.

Measured against every bull market dating back to the 1950s, the 119% advance sits near the middle of the pack, well below the 401% gain during the 2009-2020 cycle and the 582% gain from 1987-2000.

The historical average advance for a bull market in Lerner's measurement period is 184%. Of the 10 prior bull markets, six lasted longer than four years.

Among bull markets that reached this stage, the fifth year produced an average return of 12% and a median return of 15%.

"The weight of the evidence remains supportive as the bull market enters its fifth year," Lerner wrote. "Continued economic growth, resilient corporate profits, and a meaningful reset in valuations provide a solid foundation for maintaining a constructive stance. At the same time, history suggests investors should not get caught off guard by volatility as the cycle matures."

The bull market this year has been powered by the one-two punch of strong corporate earnings and AI optimism.

The S&P 500 ( ^GSPC ) is expected to report year-over-year earnings growth of 29.5% for the recently completed third quarter.

If that plays out, it will mark the third consecutive quarter of earnings growth above 25%, according to FactSet. It would also represent the eighth straight quarter of double-digit percentage earnings growth.

For the fourth quarter, Wall Street analysts are calling for earnings growth of 27.6%. And for all of 2026, analysts are predicting year-over-year earnings growth of 32.4%.

Earnings estimates for 2027 are already on the rise, especially for tech names amid unrelenting AI demand.

About 40% of the year-to-date revisions to S&P 500 earnings estimates for 2026 are attributable to the semiconductor and hardware industries, according to a new analysis from Barclays strategist Venu Krishna.

A substantial 75% of the year-to-date estimate revisions for 2027 come from the semiconductor and hardware sectors.

Brian Sozzi is Yahoo Finance's Executive Editor, host of the Sozzi Unleashed morning show and the Power Players with Brian Sozzi podcast, and a member of Yahoo Finance's editorial leadership team. Follow Sozzi on X @BrianSozzi , Instagram , and LinkedIn . Tips on stories? Email brian.sozzi@yahoofinance.com.