Update Guitext every frame

using javascript i wrote a scoring script accessed by other scripts, but i want to make the guitext show to counter every frame to keep an updated score. please help

 var Counter : int = 0;
 
 
 function addscore () {
       Counter++;
       guiText.text = ""+Counter; 
       if (Counter > 100){
       guiText.anchor = TextAnchor.UpperRight;
       guiText.pixelOffset = Vector2 (100,351);
 }
 }
 function Update (){
 guiText.text = ""+Counter;
 }
 
 
 function endlevel (){
     guiText.text = "0";
     Counter = 0;
     
 }

thanks :)