Animated Output Based On Single Input Field

I'm trying to animate an output which is calculated based on a single input value * 4.5. The calculation itself is working but I cannot figure out how to animate the value, what I'

Solution 1:

You'll probably want to use requestAnimationFrame like this:

function updateOutput() {
  var income = $("#income").val() * 4.5;
  var output = Number($("#loan").text());

  if (income !== output) {
    if (income > output)
      output += 0.5;
    else if (income < output)
      output -= 0.5;

    $("#loan").text(output);
    requestAnimationFrame(updateOutput);
  }
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<form id="ewcalc" oninput="updateOutput()">
  <input id="income" type="number" value="0" />
  <output for="income" id="loan">0</output>
</form>