diff --git a/README.md b/README.md
index 8f2897b..03345d6 100644
--- a/README.md
+++ b/README.md
@@ -62,6 +62,7 @@ interface CountUpOptions {
   numerals?: string[]; // numeral glyph substitution
   enableScrollSpy?: boolean; // start animation when target is in view
   scrollSpyDelay?: number; // delay (ms) after target comes into view
+  scrollSpyOnce?: boolean; // run only once
 }
 ```
 
diff --git a/dist/countUp.d.ts b/dist/countUp.d.ts
index fb79c38..3b3611a 100644
--- a/dist/countUp.d.ts
+++ b/dist/countUp.d.ts
@@ -15,6 +15,7 @@ export interface CountUpOptions {
     numerals?: string[];
     enableScrollSpy?: boolean;
     scrollSpyDelay?: number;
+    scrollSpyOnce?: boolean;
 }
 export declare class CountUp {
     private endVal;
@@ -36,6 +37,7 @@ export declare class CountUp {
     duration: number;
     paused: boolean;
     frameVal: number;
+    once: boolean;
     constructor(target: string | HTMLElement | HTMLInputElement, endVal: number, options?: CountUpOptions);
     handleScroll(self: CountUp): void;
     private determineDirectionAndSmartEasing;
diff --git a/dist/countUp.js b/dist/countUp.js
index 6f113c1..ed99e2b 100644
--- a/dist/countUp.js
+++ b/dist/countUp.js
@@ -30,6 +30,7 @@ var CountUp = /** @class */ (function () {
             suffix: '',
             enableScrollSpy: false,
             scrollSpyDelay: 200,
+            scrollSpyOnce: false,
         };
         this.finalEndVal = null; // for smart easing
         this.useEasing = true;
@@ -37,6 +38,7 @@ var CountUp = /** @class */ (function () {
         this.error = '';
         this.startVal = 0;
         this.paused = true;
+        this.once = false;
         this.count = function (timestamp) {
             if (!_this.startTime) {
                 _this.startTime = timestamp;
@@ -153,7 +155,7 @@ var CountUp = /** @class */ (function () {
         }
     }
     CountUp.prototype.handleScroll = function (self) {
-        if (!self || !window)
+        if (!self || !window || self.once)
             return;
         var bottomOfScroll = window.innerHeight + window.scrollY;
         var bottomOfEl = self.el.offsetTop + self.el.offsetHeight;
@@ -161,6 +163,8 @@ var CountUp = /** @class */ (function () {
             // in view
             self.paused = false;
             setTimeout(function () { return self.start(); }, self.options.scrollSpyDelay);
+            if (self.options.scrollSpyOnce)
+                self.once = true;
         }
         else if (window.scrollY > bottomOfEl && !self.paused) {
             // scrolled past
diff --git a/dist/countUp.min.js b/dist/countUp.min.js
index 91025b6..056f821 100644
--- a/dist/countUp.min.js
+++ b/dist/countUp.min.js
@@ -1 +1 @@
-var __assign=this&&this.__assign||function(){return(__assign=Object.assign||function(t){for(var i,a=1,n=arguments.length;a<n;a++)for(var s in i=arguments[a])Object.prototype.hasOwnProperty.call(i,s)&&(t[s]=i[s]);return t}).apply(this,arguments)},CountUp=function(){function t(t,i,a){var n=this;this.endVal=i,this.options=a,this.version="2.1.0",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:"",enableScrollSpy:!1,scrollSpyDelay:200},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.count=function(t){n.startTime||(n.startTime=t);var i=t-n.startTime;n.remaining=n.duration-i,n.useEasing?n.countDown?n.frameVal=n.startVal-n.easingFn(i,0,n.startVal-n.endVal,n.duration):n.frameVal=n.easingFn(i,n.startVal,n.endVal-n.startVal,n.duration):n.countDown?n.frameVal=n.startVal-(n.startVal-n.endVal)*(i/n.duration):n.frameVal=n.startVal+(n.endVal-n.startVal)*(i/n.duration),n.countDown?n.frameVal=n.frameVal<n.endVal?n.endVal:n.frameVal:n.frameVal=n.frameVal>n.endVal?n.endVal:n.frameVal,n.frameVal=Number(n.frameVal.toFixed(n.options.decimalPlaces)),n.printValue(n.frameVal),i<n.duration?n.rAF=requestAnimationFrame(n.count):null!==n.finalEndVal?n.update(n.finalEndVal):n.callback&&n.callback()},this.formatNumber=function(t){var i,a,s,e,r=t<0?"-":"";i=Math.abs(t).toFixed(n.options.decimalPlaces);var o=(i+="").split(".");if(a=o[0],s=o.length>1?n.options.decimal+o[1]:"",n.options.useGrouping){e="";for(var l=0,h=a.length;l<h;++l)0!==l&&l%3==0&&(e=n.options.separator+e),e=a[h-l-1]+e;a=e}return n.options.numerals&&n.options.numerals.length&&(a=a.replace(/[0-9]/g,function(t){return n.options.numerals[+t]}),s=s.replace(/[0-9]/g,function(t){return n.options.numerals[+t]})),r+n.options.prefix+a+s+n.options.suffix},this.easeOutExpo=function(t,i,a,n){return a*(1-Math.pow(2,-10*t/n))*1024/1023+i},this.options=__assign(__assign({},this.defaults),a),this.formattingFn=this.options.formattingFn?this.options.formattingFn:this.formatNumber,this.easingFn=this.options.easingFn?this.options.easingFn:this.easeOutExpo,this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.endVal=this.validateValue(i),this.options.decimalPlaces=Math.max(this.options.decimalPlaces),this.resetDuration(),this.options.separator=String(this.options.separator),this.useEasing=this.options.useEasing,""===this.options.separator&&(this.options.useGrouping=!1),this.el="string"==typeof t?document.getElementById(t):t,this.el?this.printValue(this.startVal):this.error="[CountUp] target is null or undefined",void 0!==window&&this.options.enableScrollSpy&&(this.error?console.error(this.error,t):(window.onScrollFns=window.onScrollFns||[],window.onScrollFns.push(function(){return n.handleScroll(n)}),window.onscroll=function(){window.onScrollFns.forEach(function(t){return t()})},this.handleScroll(this)))}return t.prototype.handleScroll=function(t){if(t&&window){var i=window.innerHeight+window.scrollY,a=t.el.offsetTop+t.el.offsetHeight;a<i&&a>window.scrollY&&t.paused?(t.paused=!1,setTimeout(function(){return t.start()},t.options.scrollSpyDelay)):window.scrollY>a&&!t.paused&&t.reset()}},t.prototype.determineDirectionAndSmartEasing=function(){var t=this.finalEndVal?this.finalEndVal:this.endVal;this.countDown=this.startVal>t;var i=t-this.startVal;if(Math.abs(i)>this.options.smartEasingThreshold){this.finalEndVal=t;var a=this.countDown?1:-1;this.endVal=t+a*this.options.smartEasingAmount,this.duration=this.duration/2}else this.endVal=t,this.finalEndVal=null;this.finalEndVal?this.useEasing=!1:this.useEasing=this.options.useEasing},t.prototype.start=function(t){this.error||(this.callback=t,this.duration>0?(this.determineDirectionAndSmartEasing(),this.paused=!1,this.rAF=requestAnimationFrame(this.count)):this.printValue(this.endVal))},t.prototype.pauseResume=function(){this.paused?(this.startTime=null,this.duration=this.remaining,this.startVal=this.frameVal,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count)):cancelAnimationFrame(this.rAF),this.paused=!this.paused},t.prototype.reset=function(){cancelAnimationFrame(this.rAF),this.paused=!0,this.resetDuration(),this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.printValue(this.startVal)},t.prototype.update=function(t){cancelAnimationFrame(this.rAF),this.startTime=null,this.endVal=this.validateValue(t),this.endVal!==this.frameVal&&(this.startVal=this.frameVal,this.finalEndVal||this.resetDuration(),this.finalEndVal=null,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count))},t.prototype.printValue=function(t){var i=this.formattingFn(t);"INPUT"===this.el.tagName?this.el.value=i:"text"===this.el.tagName||"tspan"===this.el.tagName?this.el.textContent=i:this.el.innerHTML=i},t.prototype.ensureNumber=function(t){return"number"==typeof t&&!isNaN(t)},t.prototype.validateValue=function(t){var i=Number(t);return this.ensureNumber(i)?i:(this.error="[CountUp] invalid start or end value: ".concat(t),null)},t.prototype.resetDuration=function(){this.startTime=null,this.duration=1e3*Number(this.options.duration),this.remaining=this.duration},t}();export{CountUp};
\ No newline at end of file
+var __assign=this&&this.__assign||function(){return(__assign=Object.assign||function(t){for(var i,n=1,a=arguments.length;n<a;n++)for(var s in i=arguments[n])Object.prototype.hasOwnProperty.call(i,s)&&(t[s]=i[s]);return t}).apply(this,arguments)},CountUp=function(){function t(t,i,n){var a=this;this.endVal=i,this.options=n,this.version="2.1.0",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:"",enableScrollSpy:!1,scrollSpyDelay:200,scrollSpyOnce:!1},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.once=!1,this.count=function(t){a.startTime||(a.startTime=t);var i=t-a.startTime;a.remaining=a.duration-i,a.useEasing?a.countDown?a.frameVal=a.startVal-a.easingFn(i,0,a.startVal-a.endVal,a.duration):a.frameVal=a.easingFn(i,a.startVal,a.endVal-a.startVal,a.duration):a.countDown?a.frameVal=a.startVal-(a.startVal-a.endVal)*(i/a.duration):a.frameVal=a.startVal+(a.endVal-a.startVal)*(i/a.duration),a.countDown?a.frameVal=a.frameVal<a.endVal?a.endVal:a.frameVal:a.frameVal=a.frameVal>a.endVal?a.endVal:a.frameVal,a.frameVal=Number(a.frameVal.toFixed(a.options.decimalPlaces)),a.printValue(a.frameVal),i<a.duration?a.rAF=requestAnimationFrame(a.count):null!==a.finalEndVal?a.update(a.finalEndVal):a.callback&&a.callback()},this.formatNumber=function(t){var i,n,s,e,r=t<0?"-":"";i=Math.abs(t).toFixed(a.options.decimalPlaces);var o=(i+="").split(".");if(n=o[0],s=o.length>1?a.options.decimal+o[1]:"",a.options.useGrouping){e="";for(var l=0,h=n.length;l<h;++l)0!==l&&l%3==0&&(e=a.options.separator+e),e=n[h-l-1]+e;n=e}return a.options.numerals&&a.options.numerals.length&&(n=n.replace(/[0-9]/g,function(t){return a.options.numerals[+t]}),s=s.replace(/[0-9]/g,function(t){return a.options.numerals[+t]})),r+a.options.prefix+n+s+a.options.suffix},this.easeOutExpo=function(t,i,n,a){return n*(1-Math.pow(2,-10*t/a))*1024/1023+i},this.options=__assign(__assign({},this.defaults),n),this.formattingFn=this.options.formattingFn?this.options.formattingFn:this.formatNumber,this.easingFn=this.options.easingFn?this.options.easingFn:this.easeOutExpo,this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.endVal=this.validateValue(i),this.options.decimalPlaces=Math.max(this.options.decimalPlaces),this.resetDuration(),this.options.separator=String(this.options.separator),this.useEasing=this.options.useEasing,""===this.options.separator&&(this.options.useGrouping=!1),this.el="string"==typeof t?document.getElementById(t):t,this.el?this.printValue(this.startVal):this.error="[CountUp] target is null or undefined",void 0!==window&&this.options.enableScrollSpy&&(this.error?console.error(this.error,t):(window.onScrollFns=window.onScrollFns||[],window.onScrollFns.push(function(){return a.handleScroll(a)}),window.onscroll=function(){window.onScrollFns.forEach(function(t){return t()})},this.handleScroll(this)))}return t.prototype.handleScroll=function(t){if(t&&window&&!t.once){var i=window.innerHeight+window.scrollY,n=t.el.offsetTop+t.el.offsetHeight;n<i&&n>window.scrollY&&t.paused?(t.paused=!1,setTimeout(function(){return t.start()},t.options.scrollSpyDelay),t.options.scrollSpyOnce&&(t.once=!0)):window.scrollY>n&&!t.paused&&t.reset()}},t.prototype.determineDirectionAndSmartEasing=function(){var t=this.finalEndVal?this.finalEndVal:this.endVal;this.countDown=this.startVal>t;var i=t-this.startVal;if(Math.abs(i)>this.options.smartEasingThreshold){this.finalEndVal=t;var n=this.countDown?1:-1;this.endVal=t+n*this.options.smartEasingAmount,this.duration=this.duration/2}else this.endVal=t,this.finalEndVal=null;this.finalEndVal?this.useEasing=!1:this.useEasing=this.options.useEasing},t.prototype.start=function(t){this.error||(this.callback=t,this.duration>0?(this.determineDirectionAndSmartEasing(),this.paused=!1,this.rAF=requestAnimationFrame(this.count)):this.printValue(this.endVal))},t.prototype.pauseResume=function(){this.paused?(this.startTime=null,this.duration=this.remaining,this.startVal=this.frameVal,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count)):cancelAnimationFrame(this.rAF),this.paused=!this.paused},t.prototype.reset=function(){cancelAnimationFrame(this.rAF),this.paused=!0,this.resetDuration(),this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.printValue(this.startVal)},t.prototype.update=function(t){cancelAnimationFrame(this.rAF),this.startTime=null,this.endVal=this.validateValue(t),this.endVal!==this.frameVal&&(this.startVal=this.frameVal,this.finalEndVal||this.resetDuration(),this.finalEndVal=null,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count))},t.prototype.printValue=function(t){var i=this.formattingFn(t);"INPUT"===this.el.tagName?this.el.value=i:"text"===this.el.tagName||"tspan"===this.el.tagName?this.el.textContent=i:this.el.innerHTML=i},t.prototype.ensureNumber=function(t){return"number"==typeof t&&!isNaN(t)},t.prototype.validateValue=function(t){var i=Number(t);return this.ensureNumber(i)?i:(this.error="[CountUp] invalid start or end value: ".concat(t),null)},t.prototype.resetDuration=function(){this.startTime=null,this.duration=1e3*Number(this.options.duration),this.remaining=this.duration},t}();export{CountUp};
\ No newline at end of file
diff --git a/dist/countUp.umd.js b/dist/countUp.umd.js
index c331bf2..7080212 100644
--- a/dist/countUp.umd.js
+++ b/dist/countUp.umd.js
@@ -36,6 +36,7 @@
                 suffix: '',
                 enableScrollSpy: false,
                 scrollSpyDelay: 200,
+                scrollSpyOnce: false,
             };
             this.finalEndVal = null; // for smart easing
             this.useEasing = true;
@@ -43,6 +44,7 @@
             this.error = '';
             this.startVal = 0;
             this.paused = true;
+            this.once = false;
             this.count = function (timestamp) {
                 if (!_this.startTime) {
                     _this.startTime = timestamp;
@@ -159,7 +161,7 @@
             }
         }
         CountUp.prototype.handleScroll = function (self) {
-            if (!self || !window)
+            if (!self || !window || self.once)
                 return;
             var bottomOfScroll = window.innerHeight + window.scrollY;
             var bottomOfEl = self.el.offsetTop + self.el.offsetHeight;
@@ -167,6 +169,8 @@
                 // in view
                 self.paused = false;
                 setTimeout(function () { return self.start(); }, self.options.scrollSpyDelay);
+                if (self.options.scrollSpyOnce)
+                    self.once = true;
             }
             else if (window.scrollY > bottomOfEl && !self.paused) {
                 // scrolled past
diff --git a/dist/countUp.withPolyfill.min.js b/dist/countUp.withPolyfill.min.js
index 58b520b..b69884c 100644
--- a/dist/countUp.withPolyfill.min.js
+++ b/dist/countUp.withPolyfill.min.js
@@ -1 +1 @@
-!function(){for(var t=0,i=["webkit","moz","ms","o"],n=0;n<i.length&&!window.requestAnimationFrame;++n)window.requestAnimationFrame=window[i[n]+"RequestAnimationFrame"],window.cancelAnimationFrame=window[i[n]+"CancelAnimationFrame"]||window[i[n]+"CancelRequestAnimationFrame"];window.requestAnimationFrame||(window.requestAnimationFrame=function(i){var n=(new Date).getTime(),a=Math.max(0,16-(n-t)),s=window.setTimeout(function(){return i(n+a)},a);return t=n+a,s}),window.cancelAnimationFrame||(window.cancelAnimationFrame=function(t){clearTimeout(t)})}();var __assign=this&&this.__assign||function(){return(__assign=Object.assign||function(t){for(var i,n=1,a=arguments.length;n<a;n++)for(var s in i=arguments[n])Object.prototype.hasOwnProperty.call(i,s)&&(t[s]=i[s]);return t}).apply(this,arguments)},CountUp=function(){function t(t,i,n){var a=this;this.endVal=i,this.options=n,this.version="2.1.0",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:"",enableScrollSpy:!1,scrollSpyDelay:200},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.count=function(t){a.startTime||(a.startTime=t);var i=t-a.startTime;a.remaining=a.duration-i,a.useEasing?a.countDown?a.frameVal=a.startVal-a.easingFn(i,0,a.startVal-a.endVal,a.duration):a.frameVal=a.easingFn(i,a.startVal,a.endVal-a.startVal,a.duration):a.countDown?a.frameVal=a.startVal-(a.startVal-a.endVal)*(i/a.duration):a.frameVal=a.startVal+(a.endVal-a.startVal)*(i/a.duration),a.countDown?a.frameVal=a.frameVal<a.endVal?a.endVal:a.frameVal:a.frameVal=a.frameVal>a.endVal?a.endVal:a.frameVal,a.frameVal=Number(a.frameVal.toFixed(a.options.decimalPlaces)),a.printValue(a.frameVal),i<a.duration?a.rAF=requestAnimationFrame(a.count):null!==a.finalEndVal?a.update(a.finalEndVal):a.callback&&a.callback()},this.formatNumber=function(t){var i,n,s,e,r=t<0?"-":"";i=Math.abs(t).toFixed(a.options.decimalPlaces);var o=(i+="").split(".");if(n=o[0],s=o.length>1?a.options.decimal+o[1]:"",a.options.useGrouping){e="";for(var l=0,u=n.length;l<u;++l)0!==l&&l%3==0&&(e=a.options.separator+e),e=n[u-l-1]+e;n=e}return a.options.numerals&&a.options.numerals.length&&(n=n.replace(/[0-9]/g,function(t){return a.options.numerals[+t]}),s=s.replace(/[0-9]/g,function(t){return a.options.numerals[+t]})),r+a.options.prefix+n+s+a.options.suffix},this.easeOutExpo=function(t,i,n,a){return n*(1-Math.pow(2,-10*t/a))*1024/1023+i},this.options=__assign(__assign({},this.defaults),n),this.formattingFn=this.options.formattingFn?this.options.formattingFn:this.formatNumber,this.easingFn=this.options.easingFn?this.options.easingFn:this.easeOutExpo,this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.endVal=this.validateValue(i),this.options.decimalPlaces=Math.max(this.options.decimalPlaces),this.resetDuration(),this.options.separator=String(this.options.separator),this.useEasing=this.options.useEasing,""===this.options.separator&&(this.options.useGrouping=!1),this.el="string"==typeof t?document.getElementById(t):t,this.el?this.printValue(this.startVal):this.error="[CountUp] target is null or undefined",void 0!==window&&this.options.enableScrollSpy&&(this.error?console.error(this.error,t):(window.onScrollFns=window.onScrollFns||[],window.onScrollFns.push(function(){return a.handleScroll(a)}),window.onscroll=function(){window.onScrollFns.forEach(function(t){return t()})},this.handleScroll(this)))}return t.prototype.handleScroll=function(t){if(t&&window){var i=window.innerHeight+window.scrollY,n=t.el.offsetTop+t.el.offsetHeight;n<i&&n>window.scrollY&&t.paused?(t.paused=!1,setTimeout(function(){return t.start()},t.options.scrollSpyDelay)):window.scrollY>n&&!t.paused&&t.reset()}},t.prototype.determineDirectionAndSmartEasing=function(){var t=this.finalEndVal?this.finalEndVal:this.endVal;this.countDown=this.startVal>t;var i=t-this.startVal;if(Math.abs(i)>this.options.smartEasingThreshold){this.finalEndVal=t;var n=this.countDown?1:-1;this.endVal=t+n*this.options.smartEasingAmount,this.duration=this.duration/2}else this.endVal=t,this.finalEndVal=null;this.finalEndVal?this.useEasing=!1:this.useEasing=this.options.useEasing},t.prototype.start=function(t){this.error||(this.callback=t,this.duration>0?(this.determineDirectionAndSmartEasing(),this.paused=!1,this.rAF=requestAnimationFrame(this.count)):this.printValue(this.endVal))},t.prototype.pauseResume=function(){this.paused?(this.startTime=null,this.duration=this.remaining,this.startVal=this.frameVal,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count)):cancelAnimationFrame(this.rAF),this.paused=!this.paused},t.prototype.reset=function(){cancelAnimationFrame(this.rAF),this.paused=!0,this.resetDuration(),this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.printValue(this.startVal)},t.prototype.update=function(t){cancelAnimationFrame(this.rAF),this.startTime=null,this.endVal=this.validateValue(t),this.endVal!==this.frameVal&&(this.startVal=this.frameVal,this.finalEndVal||this.resetDuration(),this.finalEndVal=null,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count))},t.prototype.printValue=function(t){var i=this.formattingFn(t);"INPUT"===this.el.tagName?this.el.value=i:"text"===this.el.tagName||"tspan"===this.el.tagName?this.el.textContent=i:this.el.innerHTML=i},t.prototype.ensureNumber=function(t){return"number"==typeof t&&!isNaN(t)},t.prototype.validateValue=function(t){var i=Number(t);return this.ensureNumber(i)?i:(this.error="[CountUp] invalid start or end value: ".concat(t),null)},t.prototype.resetDuration=function(){this.startTime=null,this.duration=1e3*Number(this.options.duration),this.remaining=this.duration},t}();export{CountUp};
\ No newline at end of file
+!function(){for(var t=0,i=["webkit","moz","ms","o"],n=0;n<i.length&&!window.requestAnimationFrame;++n)window.requestAnimationFrame=window[i[n]+"RequestAnimationFrame"],window.cancelAnimationFrame=window[i[n]+"CancelAnimationFrame"]||window[i[n]+"CancelRequestAnimationFrame"];window.requestAnimationFrame||(window.requestAnimationFrame=function(i){var n=(new Date).getTime(),a=Math.max(0,16-(n-t)),s=window.setTimeout(function(){return i(n+a)},a);return t=n+a,s}),window.cancelAnimationFrame||(window.cancelAnimationFrame=function(t){clearTimeout(t)})}();var __assign=this&&this.__assign||function(){return(__assign=Object.assign||function(t){for(var i,n=1,a=arguments.length;n<a;n++)for(var s in i=arguments[n])Object.prototype.hasOwnProperty.call(i,s)&&(t[s]=i[s]);return t}).apply(this,arguments)},CountUp=function(){function t(t,i,n){var a=this;this.endVal=i,this.options=n,this.version="2.1.0",this.defaults={startVal:0,decimalPlaces:0,duration:2,useEasing:!0,useGrouping:!0,smartEasingThreshold:999,smartEasingAmount:333,separator:",",decimal:".",prefix:"",suffix:"",enableScrollSpy:!1,scrollSpyDelay:200,scrollSpyOnce:!1},this.finalEndVal=null,this.useEasing=!0,this.countDown=!1,this.error="",this.startVal=0,this.paused=!0,this.once=!1,this.count=function(t){a.startTime||(a.startTime=t);var i=t-a.startTime;a.remaining=a.duration-i,a.useEasing?a.countDown?a.frameVal=a.startVal-a.easingFn(i,0,a.startVal-a.endVal,a.duration):a.frameVal=a.easingFn(i,a.startVal,a.endVal-a.startVal,a.duration):a.countDown?a.frameVal=a.startVal-(a.startVal-a.endVal)*(i/a.duration):a.frameVal=a.startVal+(a.endVal-a.startVal)*(i/a.duration),a.countDown?a.frameVal=a.frameVal<a.endVal?a.endVal:a.frameVal:a.frameVal=a.frameVal>a.endVal?a.endVal:a.frameVal,a.frameVal=Number(a.frameVal.toFixed(a.options.decimalPlaces)),a.printValue(a.frameVal),i<a.duration?a.rAF=requestAnimationFrame(a.count):null!==a.finalEndVal?a.update(a.finalEndVal):a.callback&&a.callback()},this.formatNumber=function(t){var i,n,s,e,o=t<0?"-":"";i=Math.abs(t).toFixed(a.options.decimalPlaces);var r=(i+="").split(".");if(n=r[0],s=r.length>1?a.options.decimal+r[1]:"",a.options.useGrouping){e="";for(var l=0,u=n.length;l<u;++l)0!==l&&l%3==0&&(e=a.options.separator+e),e=n[u-l-1]+e;n=e}return a.options.numerals&&a.options.numerals.length&&(n=n.replace(/[0-9]/g,function(t){return a.options.numerals[+t]}),s=s.replace(/[0-9]/g,function(t){return a.options.numerals[+t]})),o+a.options.prefix+n+s+a.options.suffix},this.easeOutExpo=function(t,i,n,a){return n*(1-Math.pow(2,-10*t/a))*1024/1023+i},this.options=__assign(__assign({},this.defaults),n),this.formattingFn=this.options.formattingFn?this.options.formattingFn:this.formatNumber,this.easingFn=this.options.easingFn?this.options.easingFn:this.easeOutExpo,this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.endVal=this.validateValue(i),this.options.decimalPlaces=Math.max(this.options.decimalPlaces),this.resetDuration(),this.options.separator=String(this.options.separator),this.useEasing=this.options.useEasing,""===this.options.separator&&(this.options.useGrouping=!1),this.el="string"==typeof t?document.getElementById(t):t,this.el?this.printValue(this.startVal):this.error="[CountUp] target is null or undefined",void 0!==window&&this.options.enableScrollSpy&&(this.error?console.error(this.error,t):(window.onScrollFns=window.onScrollFns||[],window.onScrollFns.push(function(){return a.handleScroll(a)}),window.onscroll=function(){window.onScrollFns.forEach(function(t){return t()})},this.handleScroll(this)))}return t.prototype.handleScroll=function(t){if(t&&window&&!t.once){var i=window.innerHeight+window.scrollY,n=t.el.offsetTop+t.el.offsetHeight;n<i&&n>window.scrollY&&t.paused?(t.paused=!1,setTimeout(function(){return t.start()},t.options.scrollSpyDelay),t.options.scrollSpyOnce&&(t.once=!0)):window.scrollY>n&&!t.paused&&t.reset()}},t.prototype.determineDirectionAndSmartEasing=function(){var t=this.finalEndVal?this.finalEndVal:this.endVal;this.countDown=this.startVal>t;var i=t-this.startVal;if(Math.abs(i)>this.options.smartEasingThreshold){this.finalEndVal=t;var n=this.countDown?1:-1;this.endVal=t+n*this.options.smartEasingAmount,this.duration=this.duration/2}else this.endVal=t,this.finalEndVal=null;this.finalEndVal?this.useEasing=!1:this.useEasing=this.options.useEasing},t.prototype.start=function(t){this.error||(this.callback=t,this.duration>0?(this.determineDirectionAndSmartEasing(),this.paused=!1,this.rAF=requestAnimationFrame(this.count)):this.printValue(this.endVal))},t.prototype.pauseResume=function(){this.paused?(this.startTime=null,this.duration=this.remaining,this.startVal=this.frameVal,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count)):cancelAnimationFrame(this.rAF),this.paused=!this.paused},t.prototype.reset=function(){cancelAnimationFrame(this.rAF),this.paused=!0,this.resetDuration(),this.startVal=this.validateValue(this.options.startVal),this.frameVal=this.startVal,this.printValue(this.startVal)},t.prototype.update=function(t){cancelAnimationFrame(this.rAF),this.startTime=null,this.endVal=this.validateValue(t),this.endVal!==this.frameVal&&(this.startVal=this.frameVal,this.finalEndVal||this.resetDuration(),this.finalEndVal=null,this.determineDirectionAndSmartEasing(),this.rAF=requestAnimationFrame(this.count))},t.prototype.printValue=function(t){var i=this.formattingFn(t);"INPUT"===this.el.tagName?this.el.value=i:"text"===this.el.tagName||"tspan"===this.el.tagName?this.el.textContent=i:this.el.innerHTML=i},t.prototype.ensureNumber=function(t){return"number"==typeof t&&!isNaN(t)},t.prototype.validateValue=function(t){var i=Number(t);return this.ensureNumber(i)?i:(this.error="[CountUp] invalid start or end value: ".concat(t),null)},t.prototype.resetDuration=function(){this.startTime=null,this.duration=1e3*Number(this.options.duration),this.remaining=this.duration},t}();export{CountUp};
\ No newline at end of file
diff --git a/src/countUp.ts b/src/countUp.ts
index dc6aeed..0c1439d 100644
--- a/src/countUp.ts
+++ b/src/countUp.ts
@@ -16,6 +16,7 @@ export interface CountUpOptions { // (default)
   numerals?: string[]; // numeral glyph substitution
   enableScrollSpy?: boolean; // start animation when target is in view
   scrollSpyDelay?: number; // delay (ms) after target comes into view
+  scrollSpyOnce?: boolean; // run only once
 }
 
 // playground: stackblitz.com/edit/countup-typescript
@@ -36,6 +37,7 @@ export class CountUp {
     suffix: '',
     enableScrollSpy: false,
     scrollSpyDelay: 200,
+    scrollSpyOnce: false,
   };
   private el: HTMLElement | HTMLInputElement;
   private rAF: any;
@@ -52,6 +54,7 @@ export class CountUp {
   duration: number;
   paused = true;
   frameVal: number;
+  once = false;
 
   constructor(
     target: string | HTMLElement | HTMLInputElement,
@@ -101,13 +104,15 @@ export class CountUp {
   }
 
   handleScroll(self: CountUp): void {
-    if (!self || !window) return;
+    if (!self || !window || self.once) return;
     const bottomOfScroll = window.innerHeight +  window.scrollY;
     const bottomOfEl = self.el.offsetTop + self.el.offsetHeight;
     if (bottomOfEl < bottomOfScroll && bottomOfEl >  window.scrollY && self.paused) {
       // in view
       self.paused = false;
       setTimeout(() => self.start(), self.options.scrollSpyDelay);
+      if (self.options.scrollSpyOnce)
+        self.once = true;
     } else if ( window.scrollY > bottomOfEl && !self.paused) {
       // scrolled past
       self.reset();