JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-countto/1.2.0/jquery.countTo.js"></script>

<div class="empty-space">
scroll down...
</div>

<div class="stats">
<h1 data-from="200" data-to="2000" data-speed="1750" data-refresh-interval="50">200</h1>
</div>

<div class="empty-space">

</div>

CSS

.empty-space{
  height: 500px;
}

JavaScript

$(function() {
    var oTop = $('.stats').offset().top - window.innerHeight;
    $(window).scroll(function(){

        var pTop = $('body').scrollTop();
        if( pTop > oTop ){
              start_count();
        }
    });
});
var executed = false; // <= variable to false.

function start_count(){


if (!executed){ // <= make sure it didn't executed before.

    $('.stats h1').countTo({
      onComplete: function() {
        var elementToPrepend = '<span style="margin-left:4px;">+</span>';
        $(elementToPrepend).hide().appendTo(this).fadeIn();

      }
    });
    
    executed = true; // <= the count() function already executed
    
}

}