Hi ikegami, could you enlighten me what is wrong on using List::Util? the following code works fine, after I corrected the hash provided: 
foreach my $y (sort keys %Year) {
  my $min_y = List::Util::min values %{ $Year{$y} };
  print "min of [$y] is [$min_y]\n";
}

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Edit: this works for sure only if you doesn't care about the month of the min/max value.

In reply to Re^2: min and max in a hash of hash by wwe
in thread min and max in a hash of hash by nagalenoj

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