Displaying a static variable from another script with OnGUI

Hello I am trying to access a variable from another script and then display it on OnGUI. In one script called Career_Variables I have 6 variables : Fame, Fame_level, money, Races_Completed, Races_won, Races_lost. I have already been able to access the variables from Career_Variables in another script so I dont think that its a problem with gameobject.FindObject.GetComponent

Here's the code of the script with the GUI

 using UnityEngine;
 using System.Collections;
 
 public class Career_GUI : Career_Variables {
     
     Texture StartRacing;
     GUIStyle bigger_option_GUI_Style;
     GUIStyle smaller_option_GUI_Style;
     GUIStyle two_smaller_option_GUI_Style;
     
     
     void Start () {
 
     }
     
     void Update () {
         Career_Variables career = GameObject.Find("Background Camera").GetComponent<Career_Variables>();
 
     }
     
     void OnGUI()
     {
         GUI.Label(new Rect(605, 8, 20, 20),  money.ToString());
         GUI.Label(new Rect(850, 100, 20, 20),  Races_Completed.ToString(), smaller_option_GUI_Style);
         GUI.Label(new Rect(1155, 130, 20, 20),  Fame.ToString(), two_smaller_option_GUI_Style);
         GUI.Label(new Rect(1319, 100, 20, 20),  Races_won.ToString(), two_smaller_option_GUI_Style);
         if (GUI.Button(new Rect(5,140,265,180), StartRacing))
             Application.LoadLevel ("Level Select");
     }
 }

And this is the code of the class that holds the variables

 using UnityEngine;
 using System.Collections;
 
 public class Career_Variables : MonoBehaviour {
 
 static public int Fame;
 static public int Fame_level;
 static public int money = 20000;
 static public int Races_Completed;
 static public int Races_won;
 static public int Races_lost;
 
 void Start () {
 
 }
 
 void Update () {
 
 }
 
 
 }

I keep getting the errors

NullReferenceException: Object reference not set to an instance of an object

UnityEngine.GUI.Label (Rect position, UnityEngine.GUIContent content, UnityEngine.GUIStyle style) UnityEngine.GUI.Label (Rect position, System.String text, UnityEngine.GUIStyle style) Career_GUI.OnGUI () (at Assets/Scripts/CSharpScripts/Career_GUI.cs:27) and

UnityException: You are not allowed to call this function when declaring a variable.

Move it to the line after without a variable declaration. If you are using C# don't use this function in the constructor or field initializers, Instead move initialization to the Awake or Start function. Career_GUI..ctor () I've tried to decode these errors but i'm totally confused. All help will be appreciated Thank you in Advance