Object reference not set to an instance of an object

Hey guys, I cannot figure out why this error is occurring, I've looked at other people who have reported the same error but it appears to be completely unrelated. Any help is appreciated! =) Below are the 2 files where the problem occurs, Unity says it's on this line: goldDisplay.text = "Gold: " + CurrencyConverter.Instance.GetCurrencyIntoString(gold);

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class Click : MonoBehaviour {
6.  
7.     public UnityEngine.UI.Text gpc;
8.     public UnityEngine.UI.Text goldDisplay;
9.     public float gold = 0;
10.     public int goldPerClick = 1;
11.    
12.     // Update is called once per frame
13.     void Update () {
14.         goldDisplay.text = "Gold: " + CurrencyConverter.Instance.GetCurrencyIntoString(gold);
15.         gpc.text = goldPerClick + " gold/click";
16.     }
17.  
18.     public void Clicked () {
19.         gold += goldPerClick;
20.  
21.     }
22. }
23.  

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class CurrencyConverter : MonoBehaviour {
6.  
7.     private static CurrencyConverter instance;
8.     public static CurrencyConverter Instance{
9.         get{
10.             return instance;
11.         }
12.     }
13.  
14.     void Awake(){
15.         CreateInstance ();
16.     }
17.  
18.     void CreateInstance(){
19.         if (instance == null) {
20.             instance = this;
21.         }
22.     }
23.  
24.     public string GetCurrencyIntoString(float valueToConvert) {
25.         string[] suffixes = {"k", "m", "b", "t", "q"};
26.         int place = 0;
27.         if (valueToConvert >= 1000) {
28.             while (valueToConvert >= 1000) {
29.                 valueToConvert /= 1000;
30.                 place++;
31.             }
32.         } else {
33.             return "" + valueToConvert;
34.         }
35.         return (valueToConvert).ToString ("f3") + suffixes [place - 1];
36.     }
37. }
38.