The current S&P 500 (SPX) advance has been closely linked to enthusiasm around artificial intelligence, with several large technology and communications companies identified as major beneficiaries. Historical datasets that classify S&P 500 (SPX) bull and bear cycles typically rank past advances by duration, including the World War II and post‑war bull market from 1942 to 1946 at roughly 1,492 days. Longer episodes such as the late‑1987 to 2000 expansion and the 2009 to 2020 cycle are also commonly cited.
In this framework, some analysts describe a scenario in which the present AI‑supported upswing has already lasted around 1,395 days and would need roughly 98 additional days without a bear‑market‑style drawdown to exceed the 1942‑1946 episode in length. That numerical path is conditional rather than confirmed, and the ranking itself is highly sensitive to how a bull market is defined and which historical dataset is used.
If an AI‑linked S&P 500 (SPX) bull were to persist long enough to reach such duration milestones, it would be consistent with ongoing investor optimism toward AI infrastructure and applications. Under that scenario, mega‑cap constituents with direct AI exposure such as NVIDIA (NVDA), Microsoft (MSFT), Alphabet (GOOGL), and Meta Platforms (META) could remain central to index performance, given their roles in GPUs, cloud computing, and large‑scale AI deployment.
Terminology
- 01Bull market: Sustained price advance, often defined as 20%+ gain from prior significant low.
- 02Bear market: Extended price decline, often defined as 20%+ drop from a recent peak.
References
- https://www.businessinsider.com/stock-market-outlook-sp500-technical-analysis-bull-market-signals-2026-7
- https://markets.businessinsider.com/index/s&p_500
- https://old.yardeni.com/wp-content/uploads/BullBearTables.pdf
- https://www.finder.com/uk/share-trading/share-trading-research/biggest-bull-markets-in-history
- https://finance.yahoo.com/news/long-might-p-500-bull-080000288.html