foreach $count ( sort keys %data ){
# there's a better notation for this but $data{$count}->@
# never works for my foreachs ;->
  foreach $type_hash ( @{ $data{$count} } ) {
    print "$count";
   # just to make it easier to see, loop through the keys
   # for the type hash in your order. NB type_hash is 
   # hash ref ($$type_hash)
    foreach $val ( (qw(type a_point z_point error) ) ) {
      print " --> $$type_hash{$val}";
    }           # foreach val
    print "\n";
  }             # foreach type_hash
}               # foreach count

##</code><code>##

while(<DATA>) {
  chomp;
  my ($count, $type, $a_point, $z_point, $error) 
       = split(/\|/);
  push @{ $data{$count} }, {type => $type, 
                 a_point => $a_point, z_point => $z_point,
                 error => "$error",
                 };
}    # while DATA