Show the int/float value in GUI.Label

Hi!

I have a float, it changes over time. I want to show/write out the value of this float in a GUI.Label. The float is nanometersinglerun. This is the code:

 using UnityEngine;
 using System.Collections;
 
 public class NewBehaviourScript : MonoBehaviour {
     public static float nanometersinglerun = 0;
     // Use this for initialization    
     
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         nanometersinglerun = Time.timeSinceLevelLoad;
            
     }
     
     void OnGUI () {
         GUI.Label (new Rect (50, 25, 100, 30), nanometersinglerun);    
     }
     
 }

When i try to start, it says: The best overloaded method match for 'UnityEngine.GUI.Label(UnityEngine.Rect, string)' has some invalid argument

and

Argument '#2' cannot convert 'float' expression to type 'string'

Both errors are at (19,17)

When i put the nanometersingletime into '' '', it works, but shows me ''nanometersingletim'' not the value.

Thanks!