diff --git a/MapControl/Shared/Map.cs b/MapControl/Shared/Map.cs
index c92369e0..bfd0d253 100644
--- a/MapControl/Shared/Map.cs
+++ b/MapControl/Shared/Map.cs
@@ -45,7 +45,7 @@ namespace MapControl
             var zoomLevel = TargetZoomLevel + MouseWheelZoomDelta * delta;
             var animated = false;
 
-            if (delta >= 1d)
+            if (delta <= -1d || delta >= 1d)
             {
                 // Zoom to integer multiple of MouseWheelZoomDelta when the event was raised by a
                 // mouse wheel or by a large movement on a touch pad or other high resolution device.