Try:
  $("#totalVisitorsCurrentDay").text(totalVisCurrDay);
    $("#totalVisitorsPastDay").text(totalVisPasDay+"https://stackoverflow.com/"+(100-(totalVisPasDay*100/totalVisCurrDay)).toFixed(2)+"%");
    $("#totalVisitorsPastWeek").text(totalVisPasWeek+"https://stackoverflow.com/"+(100-(totalVisPasWeek*100/totalVisCurrDay)).toFixed(2)+"%");
5
solved Show + or – percentage value for the total displayed