No number format in tfoot after export to excel

rahmatsetiawan

I have an issue in tfoot, after export the list to excel, all of the records are written in number format except the data in tfoot.

in excel

i have used footer callback too, something like this:

footerCallback: function (tfoot, data, start, end, display) {
        var $th = $(tfoot).find('td').eq(1);
        $th.text($.fn.dataTable.render.number(',', ',').display($th.text()))
      },

the result is written with comma separator in display, but the format is missing after export the data.
i dont know whats wrong, could you help me?

thank you