I wonder also how the situation of Norway as a whole is? And is there a chart for other countries?
In 1946, there were 161 fatalities and 675 gravely injured. This grew more or less linearly to 1971, with 533 fatalities and 4069 gravely injured. Since then it has fallen, again more or less linearly, to 108 fatalities and 602 gravely injured in 2018.
Numbers for 2019 are not out yet, as statistics for december have yet to be released.
[1]: ssb.no