[oldalum]

For the 3-year, 5-year and 10-year periods, the returns for endowments are below the ROI for the S&P 500

 no major institution would invest 100% of its endowment in equities because there would be too much volatility. They count on spending some amount each year from the endowment, and in a down year they wouldn't want to have to sell too much to do so. The SMC compares its performance (favorably) to a 70/30 equity/bonds index benchmark. I don't see any way to know how close that approximates its actual investments, but it's probably not too far off. The pie chart shows fixed income and cash are about 9% of investments, "real assets" about 11%, and "Absolute Return" 18% which probably has some bonds-like components. The rest is equity, which is overall probably somewhere between 62% and 80%. 

(BTW I'm not against index investing, for equities I'm a nearly 100% index investor myself)

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 in 2008/2009 the return was negative 27%.

That's actually the change in the value of the endowment from the beginning of the fiscal year to the end, which reflects return on investment minus money spent from the endowment on operations. So the return on investment was maybe around -23%. But your point is well taken, that is more downside volatility than desired!

[oldalum]

For the 3-year, 5-year and 10-year periods, the returns for endowments are below the ROI for the S&P 500

 no major institution would invest 100% of its endowment in equities because there would be too much volatility. They count on spending some amount each year from the endowment, and in a down year they wouldn't want to have to sell too much to do so. The SMC compares its performance (favorably) to a 70/30 equity/bonds index benchmark. I don't see any way to know how close that approximates its actual investments, but it's probably not too far off. The pie chart shows fixed income and cash are about 9% of investments, "real assets" about 11%, and "Absolute Return" 18% which probably has some bonds-like components. The rest is equity, which is overall probably somewhere between 62% and 80%. 

(BTW I'm not against index investing, for equities I'm a nearly 100% index investor myself)

---

 in 2008/2009 the return was negative 27%.

That's actually the change in the value of the endowment from the beginning of the fiscal year to the end, which reflects return on investment minus money spent from the endowment on operations. So the return on investment was maybe around -23%. But your point is well taken, that is more downside volatility than desired!