As referenced in an earlier post, I have kept detailed notes from the beginning of my current Labyrinth Lord campaign. Below are the statistics I've gathered from 6 years of play.
LL Stats Dec 2011-Dec 2017
Sessions Played: 125
Total PCs Played: 117
Total PCs Deaths: 115
Kills Per Session: 1.01
Mortality Rate: 98.3%
This first graph shows the number of LL sessions we've played each year, along with the number of kills. 2017 was a relatively thin year for us (my off-week DCC game has been getting a lot of traction & often took over LL weeks). But even when considering this, there were very few kills. 2017 was our first year under 0.8 kills per session- we only averaged one kill every 5th session. I'm ashamed of myself...
I also track every character played (and killed) in the campaign, including their class & race.
Note that a number of characters have been raised (and sometimes killed again), allowing for mortality rates above 100%.
Survivability is a stat started tracking in 2013. It is obtained by subtracting the percentage of total kills for this race (or class) from the total percentage of characters played of this race (or class). Now that I've been tracking this stat for four full years, some trends are starting to appear, particularly in Race.
We're playing with Labyrinth Lord rules, but outside of a few adventures I've written, they're all 1st edition AD&D and Basic adventures.