....
my $sth = $dbh->prepare($sql);
$sth->execute() || die $sth->errstr;

#test values here:::
#use Data::Dumper;
#my $array_ref = $sth->fetchall_arrayref;
#print Dumper $array_ref;
#end test:::

my $array_ref = $sth->fetchall_arrayref();

  foreach $row (@$array_ref)
    {
    ($type, $total) = @$row;
    if ($type eq "A"){$a = $total;}
    if ($type eq "B"){$b = $total;}
    if ($type eq "C"){$c = $total;}
    if ($type eq "D"){$d = $total;}
    if ($type eq "W"){$w = $total;}
    }

$total = $a + $b + $c + $d + $w;

print "$w\n";
print "$total\n";