Easing but not perfect

1

i add ease for my MC but it doesn’t work elasicly. so what is the problem?
here is my code.


cir.onEnterFrame = function(){
	this._x = this._x + (_root._xmouse - this._x) * .2;	
	this._y = this._y + (_root._ymouse - this._y) * .2;	
}

and here is the i copied from onesome’s AS.



cir.onEnterFrame=function(){
	if (_root._xmouse == this._x){
		this._x += _root._xmouse;
		this._y += _root._ymouse;
		isFollowing = true;
	}else if (isFollowing){
		speedx = (_root._xmouse - last_xmouse) * .8;
		speedy = (_root._ymouse - last_ymouse) * .8;
		this._x = _root._xmouse + speedx;
		this._y = _root._ymouse + speedy;
		isFollowing = false;
	}else{
		speedx += (_root._xmouse - this._x) * .8;
		speedy += (_root._ymouse - this._y) * .8;
		speedx *= .7;
		speedy *= .7;
		this._x += speedx;
		this._y += speedy;
	}
	last_xmouse = _root._xmouse;
	last_ymouse = _root._ymouse;

}

but i think this one is so old. and i tried alot.
but i cann’t get. any suggestions?