Hi,
Use this for F column:
=IFERROR(SUBSTITUTE(F4,"DR","")*-1,"")
and this for Column G:
=IFERROR(SUBSTITUTE(G5,"CR","")*1,"")
or single formula for both columns:
=IFERROR(IF(ISNUMBER(SEARCH("dr",F4)),SUBSTITUTE(F4,"DR","")*-1,SUBSTITUTE(F4,"CR","")*1),"")
Regards,