Dru's Notes

Each day I open a board with my business numbers and ask one question of each: am I above or below my 30-day median? John Walker's bathroom scale shows why one day is the wrong unit.

Show Notes

Each day I open a board with my business numbers and ask one question of each: am I above or below my 30-day median? John Walker's bathroom scale shows why one day is the wrong unit.

Featuring: John Walker

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Chapters:

(00:00) The 30-day median question
(00:11) Why business numbers swing
(00:21) John Walker and the bathroom scale
(00:47) The moving average
(00:58) A good day can hide a bad month

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Creators and Guests

Host
Dru Riley
Founder of Trends.vc
JW
Guest
John Walker
Featured in Dru's Notes: Why I've Stopped Judging My Business by 1 Day.

What is Dru's Notes?

One mental model each day in a few minutes. Habits, business, building products and thinking clearly. From Dru Riley, founder of Trends.vc.

Each day I open a board with my business numbers and ask one question of each: am I above or below my 30-day median?

Above it, I'm doing better than usual.

Numbers jump around, often for reasons that have little to do with what we did. These swings are part of running a business.

What I want to know is whether I'm moving in the right direction.

A programmer named John Walker tells a version of this in The Hacker's Diet. In January 1988 he set out to go from 215 pounds to 145.

Along the way his weight swung by several pounds from one day to the next, mostly from water. A good week could still end on a higher number.

He called the bathroom scale "a modern instrument of psychological torture, an engine of confusion and despair."

John started plotting a moving average instead. Each morning's weight nudged the line a little. He judged his progress by the average.

By November he weighed 145.

A good day can hide a bad month. A bad day can hide a good one.

What goal could you judge by the month instead of a day?