-my $tmpyear = $year - 1;
-my $tmpmonth = $month - 3;
-$filterdate1 = format_date($tmpyear . "-" . $month . "-" . $day);
-$filterdate2 = format_date($year . "-" . $tmpmonth . "-" . $day);
+$filterdate1 = format_date(sprintf("%-04.4d-%-02.2d-%02.2d", Add_Delta_YM($year, $month, $day, -1, 0)));
+$filterdate2 = format_date(sprintf("%-04.4d-%-02.2d-%02.2d", Add_Delta_YM($year, $month, $day, 0, -3)));