JSFiddle - React, Tailwind, and code Playground

HTML

<p id="sum">total: <span>0</span></p>
<button>Start</button>

JavaScript

var sum = $('#sum span'),
        but = $('button'),
        timer;
function startCountdown(){
  var startFrom = 0.00011;
  sum.text(startFrom).show();
  timer = setInterval(function(){
      sum.text(+sum.text()+startFrom);
  },1000);
}
but.click(startCountdown);