The S&P 500 is having its second-best decade ever

The S&P 500 has gained 141% since the end of 2019, putting the index on pace for one of the strongest decades in its history, the Kobeissi Letter said. If the current pace holds through 2029, the firm's math puts the decade's cumulative gain at roughly 277%, which would rank as the second-best decade on record.

“US stocks are having one of their best decades in history: The S&P 500 has gained +141.0% so far since the end of 2019. If this pace continues, the index will finish the decade with a cumulative gain of roughly +277%. This would rank as the 2nd-best decade on record, trailing only the +316% return posted during the 1989-1999 Dot-Com Boom. This would also surpass the +257% gain seen during the postwar boom decade of 1949-1959. By comparison, between 2010 and 2020, the S&P 500 returned +190% following the 2008 Financial Crisis. The 2020s are shaping up to be one of the greatest decades in US equity market history.”

— The Kobeissi Letter, X, Aug. 20, 2026

• S&P 500 gain since end of 2019: +141.0%
• Projected full-decade gain at current pace: roughly +277%
• Best decade on record: 1989-1999, +316% (dot-com boom)
• Third-best on this projection: 1949-1959, +257% (postwar boom)
• Prior decade for comparison: 2010-2020, +190% (post-2008 recovery)

A run like that needs more than one sector carrying it, and the current stretch has had several: a recovery from the 2020 pandemic crash, a multi-year run in mega-cap technology stocks tied to AI spending, and resilient corporate earnings through a stretch of rate hikes that many investors expected to hit stocks harder than it did. The 1990s comparison is a reasonable one on paper. Both decades feature a small group of large, fast-growing companies pulling a disproportionate share of the index's total return, though whether that ends the way the dot-com decade did remains the open question hanging over every version of this chart.

The same account flagged a separate move worth reading alongside the stock rally. Gold and silver added a combined $1.3 trillion in market capitalization the same morning the Treasury expanded its bond buyback program, doubling the size of its liquidity-support operations for longer-dated debt. The Kobeissi Letter tied the two moves together directly, framing the metals rally as a reaction to the same liquidity signal moving stocks and, on the same day, bitcoin: "The Fed can no longer contain yields, and the US government cannot afford higher yields. Asset owners will be the only winners."

That framing treats stocks, gold, and bitcoin as different expressions of the same trade rather than competing ones, all of them benefiting when investors read government liquidity support as a signal that cash and bonds are the assets losing ground. A decade-long equity run and a single morning's move in gold and silver are different kinds of evidence, one built on years of earnings and price data, the other on a same-day reaction to one Treasury announcement, and treating them as proof of the identical thesis is a bigger claim than either data point supports on its own.

Nothing here should be taken as financial advice — just information to consider.