code: function(v, date1904) {
        if (date1904) v += 1462;
        var epoch = Date.parse(v);
        var result = (epoch - new Date(Date.UTC(1899, 11, 30))) / (24 * 60 * 60 * 1000);
        return Math.floor(result);
      }
docs: Formats datetimes for compatibility with Excel
  @memberof TableExport.prototype
  @param v {Number}
  @param date1904 {Date}
  @returns {Number} epoch time