Is it normal for people to hit their heads, like not frequently, but like every now and then?

Hi Jay,
This figure is definitely tracked by actuary’s who calculate the insurance cover for many commercial enterprises as well as government consultants who provide modeling to the government of the day with regard to tracking various data points which will help it to govern...
In the past definitely Yes… pre-industrial war such as hand to hand combat there is definite indications that there was a high level of these types of injuries. However there are no real records with regard to the building safety practices during the rise of the city states to the regional states.
During the industrial revolution… with regard again to wars such as the civil war in America, WW 1 and 2 through last century we have a patchwork of data outlining and sketching a period of high injuries. There is also a similar record of various major building projects etc. which give a epileptic view of this period.
Currently during modern times in so called economically 1st world countries with the proper safety policies, legislation, and enforcement we are as a society reducing the number of possible injuries and with the help of inventions and innovations developing better methods and processes for treating such injuries…

IMHO…