If you can control how the hash is created, you could enforce a desired ordering using Tie::IxHash:

use strict;
use warnings;

use Tie::IxHash;
tie my %hash, "Tie::IxHash";
%hash = (
    Number  => '11',
    EX      => 'ArraySite',
    AM      => 'IOPort',
    PLE     => 'AddressGroup',
);
for (keys %hash) { print "$_ => $hash{$_}\n" }

__END__

Number => 11
EX => ArraySite
AM => IOPort
PLE => AddressGroup
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Update: Running a Super Search (?node_id=3989;HIT=hash%20order;re=N) yields (among many other relevant nodes) Best method to order a hash of arrays.