Thanks for the reply.

The @occurrences is actually a hash of arrray's.

push(@{$occurrences{$ID}}, "$term1");
push(@{$occurrences{$ID}}, "$term2");
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Do you know of an easier way rather than running your code within a foreach loop?

foreach (keys (%occurrences)) {
  (@occurrences) = @{$occurrences{$_}}[
  # Do the code you posted...
} # end-foreach
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