You have two different wheel travel measurements. One is how much the axle moves as the whole suspension cycles up and down, like when driving on a road and hitting bumps. The other is actual wheel movement when articulating, one wheel drooped and the other stuffed. This can be a little different than axle travel because the axle is at an angle and the wheel is outside of the rest of the suspension components.
Shock travel is usually a little different than suspension, or axle, travel since most shocks are at some kind of an angle relative to the axle.