Credit notes of fy 17-18 in gstr 3b of fy 19-20

i had issued a credit note in fy 17-18 but i forgot to show it in gstr1 as well gstr 3b
and while filling annual return of fy17-18 i had shows it in table 4. My query is whether i can decrease my output liability of fy 19-20 against credit note of fy 17-18 or not.