var today = new Date()
var y  = dt.getYear();
if (y < 1000) y +=1900;
var f = y - 1;
var targetDate = new Date("12/31/" + " " + f) //use full year
var timeAfterTarget = Math.floor(( today.getTime() - targetDate.getTime() ) / 86400000)
var msg = " - " + timeAfterTarget + " &egrave;me jour de l'ann&eacute;e -"
document.write(msg)