Ye that's a good question on why is it a 3 month moving average, and not say a 1, 2, 3 ..., 12 month average - I made a Google Sheets covering the Sahm Rule unt

Ye that's a good question on why is it a 3 month moving average, and not say a 1, 2, 3 ..., 12 month average - I made a Google Sheets covering the Sahm Rule until 1930 (Great Depression times) (graph I linked only goes to 1959). Red is Sahm Rule. Blue is just 1 year change of Unemployment. I also added an indicator to just average across 12 months if the Sahm Rule was triggered - maybe that's better of an indicator.