Something

obj.onLoadInit = function(target:MovieClip) {
	var t_w = target._width;
	var t_h = target._height;
	var w_1prozent = t_w/100;
	var h_1prozent = t_h/100;
	//
	trace(t_w+" "+w_1prozent);
	trace(t_h+" "+h_1prozent);
	//
	target._width = 90;
	var propotion_h = h_1prozent*(target._width/w_1prozent);
	target._height = propotion_h;


};