Mouse leads on Ease

I’m trying to create a nav bar that uses AS easing. For some reason, that I can’t figure out, the mouce has a lead on the moving object the further from the center it gets. Can some help me figure this out.

see attached.

I based this on the mouse follow with easing tutorial.
http://www.kirupa.com/developer/mx/followease.htm

here is my code:

onClipEvent (load) {
_x = -160;
_y = 16;
speed = 5;
}
onClipEvent (enterFrame) {
endX = this._xmouse;
if (endX>=-160 && endX<=112);
_x += (endX-_x)/speed;
}

Thanks in advance,
Pharoh32 :hitman: