sub Compress { foreach my $KEYmonth (sort keys %{$_[0]}) { foreach my $KEYcat (sort keys %{$_[0]{$KEYmonth}}) {#cat= category foreach my $KEYsubcat (sort keys %{$_[0]{$KEYmonth}{$KEYcat}}) { $i=0; foreach my $value (@{$_[0]{$KEYmonth}{$KEYcat}{$KEYsubcat}}) { $OUTPUT{'YTD'}{$KEYcat}{$KEYsubcat}[$i++] += $value; } } } } }