S&P 500 Tops in September? – Bank of America

The first of September has arrived — the month Bank of America strategist Michael Hartnett has highlighted a simple historical template: If the current US equity bull market delivered roughly the average result of past cycles, the S&P 500 would peak near US$9,914 around September 2027. That figure comes from applying an average gain of about 177% over roughly 59 months to the last bear-market low, and treating the result as a history-based extrapolation. Hartnett has framed the broader setup as “bubble or bust,” underscoring that path and timing are uncertain.

The index’s bear-market closing low was US$3,577.03 on 12 October 2022. Multiply that by 2.77 (a 177% total return), and you arrive at about US$9,914. Add an average bull-market duration of about 59 months to the October 2022 low, and you land in September 2027.

For today’s market to rise toward the US$9,900–$10,000 area over the next two years, earnings would need to keep advancing, valuation pressure from rates and inflation would need to stay contained, and positive stories would ideally broaden beyond a handful of mega-caps. If inflation were to re-accelerate, rates were to rise, or profit expectations rolled over, the rise could be delayed or capped. Those are the same crosscurrents Hartnett emphasises when he describes the near-term backdrop.

Even if history rhymes, the reality rarely matches the average exactly. The October 2022 low and the AI-led rally already put this cycle on a faster track than some prior cases. It is more accurate to view “$9,914 by September 2027” as a way to gauge scenarios rather than something markets are definitely going to print on a particular date. Independent historical work has also predicted that a typical bull market could carry the S&P 500 toward the five-digit threshold if gains approximate long-term averages.

One practical takeaway is that investors should separate the headline number from the drivers that would make it credible. Sustained earnings growth and stable or easing real rates would argue for progress toward the hypothetical target.