my $data   = join '', <DATA>;

my $by_month = {};

while($data =~ /^(\d+).*?(\w+) +(\d+) +(\w+)/mg) {
   print "Capturing $1 $2 $3 $4\n";
   $by_month->{$1}->{$2}->{$4} += $3;
}

for my $month (1..12) {
    print "Month: $month\n";
    for my $product (qw(Shirts Shoes Caps)) {
        printf "%7s ", $product;
        for my $country (qw(Asia Australia UK)) {
            printf "%6d ", 
              $by_month->{$month}->{$product}->{$country} || 0;
        }
        print "\n";
    }
}

__DATA__
1/2/04 Shirts     32         Australia
1/9/04 Shoes      234        Asia
2/12/04 Caps      109        UK
4/4/04 Shoes      6          Asia
4/4/04 Shirts     12         Australia
5/6/04 Shirts     398        Australia

##</code><code>##

Month: 1
 Shirts      0     32      0 
  Shoes    234      0      0 
   Caps      0      0      0 
Month: 2
 Shirts      0      0      0 
  Shoes      0      0      0 
   Caps      0      0    109 
Month: 3
 Shirts      0      0      0 
  Shoes      0      0      0 
   Caps      0      0      0 
Month: 4
 Shirts      0     12      0 
  Shoes      6      0      0 
   Caps      0      0      0