diff --git a/Scales/RateScale.js b/Scales/RateScale.js
index 5be5a908d..527bfac82 100644
--- a/Scales/RateScale.js
+++ b/Scales/RateScale.js
@@ -102,12 +102,15 @@ function newRateScale () {
   }
 
   function onMouseWheel (event) {
+    let morePower = 1
+    if (event.buttons === 4) { morePower = 5 } // Mouse wheel pressed.
+
     delta = event.wheelDelta
     if (delta < 0) {
-      thisObject.heightPercentage = thisObject.heightPercentage - STEP_SIZE
+      thisObject.heightPercentage = thisObject.heightPercentage - STEP_SIZE * morePower
       if (thisObject.heightPercentage < STEP_SIZE * 3) { thisObject.heightPercentage = STEP_SIZE }
     } else {
-      thisObject.heightPercentage = thisObject.heightPercentage + STEP_SIZE
+      thisObject.heightPercentage = thisObject.heightPercentage + STEP_SIZE * morePower
       if (thisObject.heightPercentage > 150) { thisObject.heightPercentage = 200 }
     }
     event.heightPercentage = thisObject.heightPercentage
diff --git a/Scales/TimeScale.js b/Scales/TimeScale.js
index 9bd8a5372..086e45fa9 100644
--- a/Scales/TimeScale.js
+++ b/Scales/TimeScale.js
@@ -101,12 +101,15 @@ function newTimeScale () {
   }
 
   function onMouseWheel (event) {
+    let morePower = 1
+    if (event.buttons === 4) { morePower = 5 } // Mouse wheel pressed.
+
     delta = event.wheelDelta
     if (delta < 0) {
-      thisObject.lenghtPercentage = thisObject.lenghtPercentage - STEP_SIZE
+      thisObject.lenghtPercentage = thisObject.lenghtPercentage - STEP_SIZE * morePower
       if (thisObject.lenghtPercentage < STEP_SIZE) { thisObject.lenghtPercentage = STEP_SIZE }
     } else {
-      thisObject.lenghtPercentage = thisObject.lenghtPercentage + STEP_SIZE
+      thisObject.lenghtPercentage = thisObject.lenghtPercentage + STEP_SIZE * morePower
       if (thisObject.lenghtPercentage > 400) { thisObject.lenghtPercentage = 400 }
     }