Arithmetic Code Error | WordPress.org

Hello;
I added a [Text Area]- [fieldname37] field, users enter random numbers in the form of 1,6,9,8.

I also want to calculate the arithmetic average of the digits entered with the code below.

I think I’m making a mistake somewhere in the code, any suggestions?

  (function() {
    var inputValues = jQuery('[name="fieldname37"]').val();
    var numbers = inputValues.split(',').map(parseFloat);
    var sum = numbers.reduce((total, num) => total + num, 0);
    var count = numbers.length;
    var arithmetic= sum / count;

    jQuery('#calculation-kriter3').html(arithmetic);
    jQuery('.arithmetic-aciklama').html('Arithmetic : ');
    jQuery('.arithmetic-sonuc').html(arithmetic);
    
    return [arithmetic];
  })();