Issue with custom editor window zooming feature

Hi! I am trying to create a custom horizontal zooming feature for a custom editor window. The editor window has time labels across the top. I am using the scroll wheel for my zooming feature and I have noticed if I zoom out really fast sometimes my labels will flip backwards. Instead of going in the direction I want them to they go in the opposite direction. I'm assuming somehow my labelspacing is becoming less than 1. Here is my code :

 private int ZoomLevel = 1;
 private int MinZoomLevel = 1;
 private int MaxZoomLevel = 22;
 private int LabelSpacing = 6;
 
 
 private void OnGUI(){
      ....
   TimeLabels();
   if (Event.current.type == EventType.ScrollWheel)
         {
 
            AdjustZoomLevel(Event.current);
 
        }
 }

      private void TimeLabels()
 {
     if (Event.current.type == EventType.Repaint)
     {
         float DisplayNum = 0;
         float Mod5NumCounter = 0;

        
         for (int i = 0; i < EffectWindow.position.width + MaxHorizontalScrollValue; i += 2)
         {
             if (i == 0)
             {
                 Handles.DrawLine(new Vector3(LabelsStartingPointX, LabelLineStartingY), new Vector3(LabelsStartingPointX, Label10thLineHeightY));
                 GUI.Label(new Rect(LabelsStartingPointX, NumberLabelsY, NumberLabelsWidth, NumberLabelsHeight), DisplayNum.ToString());
             }
             else
             {
                 Mod5NumCounter++;
                 if (Mod5NumCounter == 5)
                 {
                     Handles.DrawLine(new Vector3((LabelsStartingPointX + (i * LabelSpacing)), LabelLineStartingY), new Vector3((LabelsStartingPointX + (i * LabelSpacing)), Label5thLineHeightY));
                 }
                 else if (Mod5NumCounter == 10)
                 {
                     Handles.DrawLine(new Vector3((LabelsStartingPointX + (i * LabelSpacing)), LabelLineStartingY), new Vector3((LabelsStartingPointX + (i * LabelSpacing)), Label10thLineHeightY));

                     if (ZoomLevel < 4 )
                     {
                         DisplayNum += 0.5f; //10f;
                     }
                     else if (ZoomLevel >= 4 && ZoomLevel < 10)
                     {
                         DisplayNum += 0.1f;
                         DisplayNum = (float)Math.Round(DisplayNum, 2);
                     }
                     else if (ZoomLevel >= 10 && ZoomLevel < 16)
                     {
                         DisplayNum += 0.05f;
                         DisplayNum = (float)Math.Round(DisplayNum, 2);
                     }
                     else if (ZoomLevel >=16)
                     {
                         DisplayNum += 0.01f;
                         DisplayNum = (float)Math.Round(DisplayNum, 2);
                     }
                   



                     GUI.Label(new Rect(LabelsStartingPointX + (i * LabelSpacing), NumberLabelsY, NumberLabelsWidth, NumberLabelsHeight), DisplayNum.ToString());
                     Mod5NumCounter = 0;
                 }
                 else
                 {
                     Handles.DrawLine(new Vector3((LabelsStartingPointX + (i * LabelSpacing)), LabelLineStartingY), new Vector3((LabelsStartingPointX + (i * LabelSpacing)), Labels1sLineHeightY));
                 }
                 

             }
         }
     }
 }
 
  private void AdjustZoomLevel(Event current)
     {
         if(ZoomLevel == MinZoomLevel && Event.current.delta.y > 0)
         {
             current.Use();
             return;
         }
         else if (ZoomLevel == MaxZoomLevel && Event.current.delta.y < 0)
         {
             current.Use();
             return;
         }
 
 
         LabelSpacing -= Event.current.delta.y;
       
         if (Event.current.delta.y > 0)
         {//zoom out
             ZoomLevel -= 1;
             if(ZoomLevel == 3)
             {
                 LabelSpacing = 12;
             }
             else if (ZoomLevel == 4)
             {
                 LabelSpacing = 3;
             }
             else if(ZoomLevel == 9)
             {
                 LabelSpacing = 18;
             }
             else if (ZoomLevel == 10)
             {
                 LabelSpacing = 3;
             }
             else if (ZoomLevel == 15)
             {
                 LabelSpacing = 18;
             }
             else if (ZoomLevel == 16)
             {
                 LabelSpacing = 3;
             }
 
         }
         else
         {//zoom in
             ZoomLevel += 1;
             if(ZoomLevel == 3)
             {
                 LabelSpacing = 12;
             }
             if (ZoomLevel == 4)
             {
                 LabelSpacing = 3;
             }
             else if(ZoomLevel == 9)
             {
                 LabelSpacing = 18;
             }
             else if (ZoomLevel == 10)
             {
                 LabelSpacing = 3;
             }
             else if (ZoomLevel == 15)
             {
                 LabelSpacing = 18;
             }
             else if (ZoomLevel == 16)
             {
                 LabelSpacing = 3;
             }     
         }
    ......
    current.Use();
 }
 
 

Now I may just be doing something stupid but it isn't always the same zoom level where things begin to go wrong. Any and all help is greatly appreciated!