TheDamian's <cite>Best Practices</cite> gives several good reasons why constant should be deprecated in favour of Readonly:

Readonly my $LONG_COUNT => 14;
Readonly my $SHORT_COUNT => 9;
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But Damian also says in his book that you should use hashes for look-up tables, rather than if/else tests. And that's definitely a look-up table.

So how about something like:

Readonly \my %THWAPP_COUNT => (
  x => 14,
  y => 9,
);
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(Adjective describing what sort of a count this is courtesy of Acme::MetaSyntactic::batman.)

Smylers