Good morning

I need to enhance this code to look for anything less than or equals to a date. This date is in Cell C1

=INDEX(Targets!$B$2:$AQ$337,MATCH($C$1+0,Targets!$A$2:$A$337,0),MATCH(A6,Targets!$B$1:$AQ$1,0))
Can the current code be adapted?

Thanks in advance

DJ