On the timescale of 30 years for gov bonds vs diversified US stocks, this is almost meaningless statement. The longer a risky asset is held, the less chance of loss you’ll have. Short-horizon returns are extremely volatile, but that volatility "mean-reverts" over time.
This is especially true for stocks vs bonds. Because the cash flows of bonds are fixed, prolonged inflation or rate spikes can deliver a loss that stays a loss, making long-term "safety" in bonds partly an illusion.
This is especially true for stocks vs bonds. Because the cash flows of bonds are fixed, prolonged inflation or rate spikes can deliver a loss that stays a loss, making long-term "safety" in bonds partly an illusion.
http://www.efficientfrontier.com/t4poi/Ch1.htm