PT4 stat

Hi friends, I entered the PT4 forum but I haven't received a response yet.
But as I know that there are very well-informed and generous people here, they can answer my question.
Hud has a stat M, which only works for MTT, does anyone know the functionality of this stat?
Can anyone give me this guidance?
I thank.

Basically tells you how many rounds a player can last based on stack size versus the size of the blinds and antes.
For more info google Harrington's M Theory