(function ($) {
    $.fn.countTo = function (options) {
        options = options || {};
        
        $(this).each(function () {
            // set options for current element
            var settings = $.extend({}, $.fn.countTo.defaults, {
                from:            $(this).data('from'),
                to:              $(this).data('to'),
                speed:           $(this).data('speed'),
                refreshInterval: $(this).data('refresh-interval'),
                decimals:        $(this).data('decimals')
            }, options);
            
            // how many times to update the value, and how much to increment the value on each update
            var loops = Math.ceil(settings.speed / settings.refreshInterval),
                increment = (settings.to - settings.from) / loops;
            
            // references & variables that will change with each update
            var self = this,
                $self = $(this),
                loopCount = 0,
                value = settings.from,
                data = $self.data('countTo') || {};
            
            $self.data('countTo', data);
            
            // if an existing interval can be found, clear it first
            if (data.interval) {
                clearInterval(data.interval);
            }
            data.interval = setInterval(updateTimer, settings.refreshInterval);
            
            // initialize the element with the starting value
            render(value);
            
            function updateTimer() {
                value += increment;
                loopCount++;
                
                render(value);
                
                if (typeof(settings.onUpdate) == 'function') {
                    settings.onUpdate.call(self, value);
                }
                
                if (loopCount >= loops) {
                    // remove the interval
                    $self.removeData('countTo');
                    clearInterval(data.interval);
          
                    value = settings.to;
                    if (typeof(settings.onComplete) == 'function') {
                        settings.onComplete.call(self, value);
                    }
          //Introduce recursion here
          const el = document.querySelector('.timer');
          el && count(el);
                }
            }
            
            function render(value) {
                var formattedValue = settings.formatter.call(self, value, settings);
                $self.html(formattedValue);
            }
        });
    };
    
    $.fn.countTo.defaults = {
        from: 0,               // the number the element should start at
        to: 0,                 // the number the element should end at
        speed: 1000,           // how long it should take to count between the target numbers
        refreshInterval: 100,  // how often the element should be updated
        decimals: 0,           // the number of decimal places to show
        formatter: formatter,  // handler for formatting the value before rendering
        onUpdate: null,        // callback method for every time the element is updated
        onComplete: null       // callback method for when the element finishes updating
    };
    
    function formatter(value, settings) {
        return value.toFixed(settings.decimals);
    }
}(jQuery));

jQuery(function ($) {
  // custom formatting example
  $('.count-number').data('countToOptions', {
    formatter: function (value, options) {
      return value.toFixed(options.decimals).replace(/\B(?=(?:\d{3})+(?!\d))/g, ',');
    }
  });
  
  // start all the timers
  //$('.timer').each(data.collection.slice(1),count);
  
  
});
//instead of the for loop above kick it off by calling count once. then rely on recursion
count(document.querySelector('.timer'));
function count(el) {
    var $this = $(el);
    el.classList.remove('timer');
    options = $.extend({}, $this.data('countToOptions') || {});
    $this.countTo(options);
  }

.counter {
    background-color:#f5f5f5;
    padding: 20px 0;
    border-radius: 5px;
}

.count-title {
    font-size: 40px;
    font-weight: normal;
    margin-top: 10px;
    margin-bottom: 0;
    text-align: center;
}

.count-text {
    font-size: 13px;
    font-weight: normal;
    margin-top: 10px;
    margin-bottom: 0;
    text-align: center;
}

.fa-2x {
    margin: 0 auto;
    float: none;
    display: table;
    color: #4ad1e5;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!------ Include the above in your HEAD tag ---------->


<link rel="stylesheet" href="https://netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.min.css">
<div class="container">
    <div class="row">
        <br/>
       <div class="col text-center">
        <h2>Bootstrap 4 counter</h2>
        <p>counter to count up to a target number</p>
        </div>
        
             
        
    </div>
        <div class="row text-center">
            <div class="col">
            <div class="counter">
      <i class="fa fa-code fa-2x"></i>
      <h2 class="timer count-title count-number" data-to="100" data-speed="1500"></h2>
       <p class="count-text ">Our Customer</p>
    </div>
            </div>
              <div class="col">
               <div class="counter">
      <i class="fa fa-coffee fa-2x"></i>
      <h2 class="timer count-title count-number" data-to="1700" data-speed="1500"></h2>
      <p class="count-text ">Happy Clients</p>
    </div>
              </div>
              <div class="col">
                  <div class="counter">
      <i class="fa fa-lightbulb-o fa-2x"></i>
      <h2 class="timer count-title count-number" data-to="11900" data-speed="1500"></h2>
      <p class="count-text ">Project Complete</p>
    </div></div>
              <div class="col">
              <div class="counter">
      <i class="fa fa-bug fa-2x"></i>
      <h2 class="timer count-title count-number" data-to="157" data-speed="1500"></h2>
      <p class="count-text ">Coffee With Clients</p>
    </div>
              </div>
         </div>
</div>