I have the feeling I'm missing a deeper question that you may have, but here's untested code for the surface question: 
sub somefunction {
   my ($href, $key) = @_;
   my %counts;
   $_->{$key} && ++$counts{$_->{$key}} for values %$href;
   return %counts;
}

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In reply to Re: Simulating a summary of a hash by ysth
in thread Simulating a summary of a hash by monarch

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