Thank you both for your contribution, indeed if I can avoid using a specific module that could be much better. This is what I tried below without success yet considering the following result: { "  " => { Feb => 0, Jan => 0, Mar => 0 } } 
@mapped = ("Account Entity Unit Jan Feb Mar",
            "Account01 Entity01 Unit01 1 2 3",
            "Account01 Entity01 Unit01 4 5 6",
            "Account01 Entity01 Unit01 7 8 9",
            "Account02 Entity02 Unit02 10 11 12");

my %group_by;
my @titles = split ' ', @mapped;

foreach (@mapped) {
    #print $_."\n";
    my @parts = split;
    #print @parts."\n";
    my %hash; @hash{ @titles } = @parts;   #don't get it
    for(qw(Jan Feb Mar)){
        $group_by{join ' ', @hash{qw(Account Entity Unit)}}{ $_ } +=+ 
+$hash{ $_ };    #don't get it either
    }
}
use Data::Dump 'dd'; dd \%group_by;

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In reply to Re^3: Group by from array by sroux
in thread Group by from array by sroux

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