A line chart shows the wide fluctuations in the cyclically adjusted price/earnings ratio, or CAPE, for the Standard & Poor’s 500 Index from 1950 to early 2024. It also shows a fluctuating range of Vanguard estimates of a separate, fair-value CAPE measurement. The chart shows that the index’s CAPE valuation has typically hovered in or near our estimates of the fair-value CAPE. It also highlights the early-2000 valuation peak amid the dot-com bubble, with CAPE at nearly 45 and valuations exceeding fair valuations at times from 1991 to January 2024. Currently, valuations are above our range of fair-value estimate.