And what about suicides, self defense and disappearences or bodies not found? Just playing devils advocate here.

Again, to make a throw back to my own local history:
With the advent of Interstates and more affordable cars, serial killers in the US increased dramatically in the 1950s, 60s and 70s, because killers could travel between different municipalities and commit multiple murders, knowing that the different counties and cities were likely not sharing information. Some of them were brazen and didn't even try to hide what they were doing, because they could be on an interstate and in another jurisidiction in 10 minutes. So in the 50s, 60s and 70s there was also a rash of "runaways" and we got the whole "kids running off to join cults" thing, when in reality, this was young people hitch hiking, getting picked up and raped and murdered, and their bodies never found. They were often not confirmed dead until a killer spills his guts on his death bed, and by that time the runaways parents were dead or senile, going to the grave thinking their kid ran off.

The above situation was not helped by the lack of national/state identification for citizens and newborns. Social Security numbers were not mandatory until the 80s as I recall. I didnt have one until I was 14. Hell, we still hear from time to time about someone who has had their kid locked in a basement for a decade and nobody ever knew there was a kid

I think it is safe to assume that in the middle ages there were a hell of a lot more murders than accounter for, and there probably a lot of suicides/accidents that were considered murders.