Noob Question

[Red Bird]

I am returning to competitive gaming after about a 20 year absence. I am currently reading the Musket & Pike Rules for the WDS games. I've come across one thing while fiddling around with scenarios and it has brought up a question.

When I right click on a unit I understand most of the values from my previous experience and reading the rules. All except one, that is.

One value is "Front XX%". What exactly does that mean. I have been unable to find it and would really like to know. Any help would be appreciated. 

As soon as I have read the rules and am comfortable with the game I will start looking for opponents.