SELECT DATE_FORMAT(`datepaid`,'%m.%Y') AS MONTH, SUM(`commission`) AS SUM
FROM `hb_aff_orders`
WHERE
 paid = 1
AND datepaid > (Date_sub((Now() - INTERVAL 13 month),INTERVAL Dayofmonth(Now()) - 1 day))
GROUP BY DATE_FORMAT(`datepaid`,'%Y%m')