I didn't know we had so many experts and mathematicians on these forums!
Btw, using the word 'statically' doesn't make you sound more legit.
On topic though, I do believe if civilizations don't come to ruin by nature, they destroy themselves. I suspect the vast majority fall in these ways.
For example, if someone wealthy or determined enough desired to get a nuke, they could. The cold war generated tons of them.
A nuclear war could be sparked, and mutually assured destruction (MAD) would be a reality for those involved...which would be everyone via alliances.
Additionally, some were
lost.
Other civilization destroying factors are meteor impacts, super volcanoes, etc.