The broader US market is only about 25% bigger than the S&P500, FWIW. (Or put another way, S&P500 is about 80% of all US equity.) They also trade in almost lockstep:

https://totalrealreturns.com/n/VFIAX,VEXAX?start=2025-01-01

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IAmBroom 4 hours ago | parent [-]

"Almost".

This is specifically one of those points in stock history where it isn't true; the heavyweights of the S&P 500 are dragging it down while the smaller companies are less affected.

	▲	loeg 24 minutes ago \| parent [-]
		I brought a graph in my earlier comment! Even over the past year, they're highly correlated. (And the S&P500 is ahead over the period -- not the other 25%.)