I don't see the need to sort all the keys in %{$data}. You can use hash slices and List::Utils::sum() to good advantage. 

use List::Utils 'sum';
sub average {
    my ($data, $first, $last) = @_;
    my %data = %$data;
    my @goodkeys = grep {exists $data{$_}} $first .. $last;
    sum( @data{ @goodkeys } ) / @goodkeys;
}

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After Compline,
Zaxo

In reply to Re: calculate average from range of hash values (optimize) by Zaxo
in thread calculate average from range of hash values (optimize) by revdiablo

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