If you just do a comparison from how large the population in a country is, your numbers will be wrong. You have to compare how many x (of whatever) there are on 100.000 persons to get a true comparison.Past decades?
17 years 1 decade 7 years
…
Hard to compare usa to finland
Usa population over 334 million finland under 6 million.
I saw that there had been 16 school shootings in the USA on March 6, which would mean 0,048 per 100.000, while 1 in Finland makes 0,18 per 100.000!