It was started in 1947 by Einstein, and other scientists. They set it at seven minutes.
It averaged about seven minutes during the cold war. Maybe ten minutes or more during the post cold war Nineties. But there were moments when it dropped to two minutes or less during both eras.
Got more unstable in the 2000s zigzagging from high to low.
But if you think of seven minute, or 420 seconds as "normal", then that means were are only four times as bad of as normal!
Only four times closer to nuclear holocaust!
Keep in mind the influences of "Woke culture" on the time setting.