Unity Automatic Resize OnGUI object

using UnityEngine;
using System.Collections;

public class GameGUI : MonoBehaviour{
public GUIStyle customGUI;

Rect ResizeGUI(Rect _rect){
 float FilScreenWidth = _rect.width / 480;
 float rectWidth = FilScreenWidth * Screen.width;
 float FilScreenHeight = _rect.height / 320;
 float rectHeight = FilScreenHeight * Screen.height;
 float rectX = (_rect.x / 480) * Screen.width;
 float rectY = (_rect.y / 320) * Screen.height;
 Debug.Log(_rect.x+" - "+_rect.y);
 //Automatic resize font size
 customGUI.fontSize=(int)rectHeight/4;
 
 //Return new position and height
 return new Rect(rectX,rectY,rectWidth,rectHeight);
}

void OnGUI(){
 GUI.Label(ResizeGUI(new Rect(190,60,100,100)), "Label position and size", customGUI);
}
}