protected function columns()
    {
        $this->data    = $this->setData();
        $column_widths = $this->getColumnWidths();
        $output        = [];
        $count         = count(reset($this->data));

        for ($i = 0; $i < $count; $i++) {
            $output[] = $this->getRow($i, $column_widths);
        }

        return $output;
    }