[JumpCrisscross]

> how long ago was the 5 day work week established as the standard?

We work unusually hard compared to our ancestors [1].

[1] https://www.youtube.com/watch?v=hvk_XylEmLo&t=1482s

[card_zero]

Or to put it another way, September 1926.

https://content.time.com/time/specials/packages/article/0,28...

Also: ancient Rome, one day off in eight, revolutionary France, one day off in ten, Han China, one day off in five.

https://en.wikipedia.org/wiki/Workweek_and_weekend#History