Saw a tweet about an Aspen house that went from $385k to $30mm in 35 years.

Good opportunity to show the mental math I do whenever I see price changes over a long period

Being approximate:

CAGR = .7 * doublings/years

.70 * 6.5 doublings/35 years

.7*.2 ~14% CAGR

(Actual CAGR is closer to 13.25%)

Doublings is just log base 2 (final value/start value)

Derivation comes from Rule 72. I use it all the time for estimating returns over decades when I look at a chart or tweet

See how I derived it here: