my $mask = "NN";
foreach my $item (LARGE_LIST) {
    $key = property($item);
    my $val = $record{ $key } || pack $mask, 0,0;
    my ($count, $flag) = unpack $mask, $val;
    $count++;
    $flag ||= condition_is_true($item);
    $record{ $key } = pack $mask, $count, $flag;
}