$month = $this->current_month - $m;
$year = $this->current_year;
if($month <= 0) { $remainder = $month; $month = 12 + $remainder; $year=$year-1; }
$month = $this->current_month - $m;
$year = $this->current_year;
if($month <= 0) { $remainder = $month; $month = 12 + $remainder; $year=$year-1; }