diff --git a/MapControl/Shared/Map.cs b/MapControl/Shared/Map.cs
index 3ecf8dfb..03938b11 100644
--- a/MapControl/Shared/Map.cs
+++ b/MapControl/Shared/Map.cs
@@ -40,13 +40,6 @@ namespace MapControl
             set => SetValue(MouseWheelZoomAnimatedProperty, value);
         }
 
-        private void OnMouseWheel(Point position, int delta)
-        {
-            // Standard mouse wheel delta value is 120.
-            //
-            OnMouseWheel(position, delta / 120d);
-        }
-
         private void OnMouseWheel(Point position, double delta)
         {
             var zoomLevel = TargetZoomLevel + MouseWheelZoomDelta * delta;
diff --git a/MapControl/WPF/Map.WPF.cs b/MapControl/WPF/Map.WPF.cs
index 2542349f..49bce609 100644
--- a/MapControl/WPF/Map.WPF.cs
+++ b/MapControl/WPF/Map.WPF.cs
@@ -26,7 +26,9 @@ namespace MapControl
 
         protected override void OnMouseWheel(MouseWheelEventArgs e)
         {
-            OnMouseWheel(e.GetPosition(this), e.Delta);
+            // Standard mouse wheel delta value is 120.
+            //
+            OnMouseWheel(e.GetPosition(this), e.Delta / 120d);
 
             base.OnMouseWheel(e);
         }
diff --git a/MapControl/WinUI/Map.WinUI.cs b/MapControl/WinUI/Map.WinUI.cs
index 636594cd..0ce141d0 100644
--- a/MapControl/WinUI/Map.WinUI.cs
+++ b/MapControl/WinUI/Map.WinUI.cs
@@ -34,7 +34,9 @@ namespace MapControl
             {
                 var point = e.GetCurrentPoint(this);
 
-                OnMouseWheel(point.Position, point.Properties.MouseWheelDelta);
+                // Standard mouse wheel delta value is 120.
+                //
+                OnMouseWheel(point.Position, point.Properties.MouseWheelDelta / 120d);
             }
         }