function DaysSince(this_date)
  {
    today  = new Date();
    todayEpoch  = today.getTime();

    target = new Date(this_date); 
    targetEpoch = target.getTime();

    daysSince = Math.floor(((todayEpoch - targetEpoch ) / (60*60*24)) / 1000);
    return daysSince;
  }