Relative dates in flex

RelativeDateUtil.as

package Assets.Applications.Includes
{
	import com.adobe.utils.DateUtil;
	
	public class RelativeDateUtil extends DateUtil
	{
		
		public static var SECONDS_IN_MINUTE:Number	 = 60;
		public static var MINUTES_IN_HOUR:Number         = 60;
		public static var HOURS_IN_DAY:Number            = 24;
		
		public static var MILLISECONDS_IN_SECOND:Number	 = 1000;
		public static var MILLISECONDS_IN_MINUTE:Number  = MILLISECONDS_IN_SECOND * SECONDS_IN_MINUTE;
		public static var MILLISECONDS_IN_HOUR:Number    = MILLISECONDS_IN_MINUTE * MINUTES_IN_HOUR;
		public static var MILLISECONDS_IN_DAY:Number     = MILLISECONDS_IN_HOUR * HOURS_IN_DAY;
		
		public static var DAYS_IN_WEEK:Number            = 7;
		public static var DAYS_IN_MONTH_MIN:Number       = 28;
		public static var DAYS_IN_MONTH_MAX:Number       = 31;
		public static var DAYS_IN_YEAR:Number            = 365;
		
		public function RelativeDateUtil()
		{
			super();
		}
		
		public static function relativeDifference(target:Date, relative:Date = null):String
		{
			if (relative == null) {
				relative = new Date();
			}
			var diff:Number = (relative.getTime() - target.getTime());
			var result:String;
			
			if (diff < MILLISECONDS_IN_SECOND) {
				result = 'a moment ago';
			} else if (diff < MILLISECONDS_IN_SECOND * 1.3) {
				result = '1 minute ago';
			} else if (diff < MILLISECONDS_IN_SECOND * 50) {
				result = Math.floor(diff / 60)+' minutes ago';
			} else if (diff < MILLISECONDS_IN_HOUR * 2) {
				result = '1 hour ago';
			} else if (diff < MILLISECONDS_IN_HOUR * (HOURS_IN_DAY / 1.02)) {
				result = Math.floor(diff / MILLISECONDS_IN_HOUR * 1.02)+' hours ago';
			} else if (diff == 1) {
				result = 'Yesterday';
			} else if (diff <= DAYS_IN_WEEK) {
				result = diff+' days ago';
			} else if (diff <= DAYS_IN_MONTH_MIN) {
				var numWeeks:Number = Math.floor(diff / DAYS_IN_WEEK);
				result = numWeeks+' weeks ago';
			} else if (diff <= DAYS_IN_YEAR) {
				var numMonths:Number = Math.floor(diff / DAYS_IN_MONTH_MIN);
				result = numMonths+' months ago';
			} else if (diff > DAYS_IN_YEAR) {
				var numYears:Number = Math.floor(diff / DAYS_IN_YEAR);
				result = numYears+' years ago';
			}
			
			return result;
		}
	}
}