Note that if you dereference the same keys several times, it might save you some runtime (not talking about readability) by createin variables for them: 
my $location = $mainHash->{$hashType}{$regionID}{MetricType}{$resultHa
+sh->{Location}};
$location->{$yearMonthDateList[$start]} += $resultHash->{Value};

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لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: $var{el} += 1 vs $var{el} = $var{el} + 1 by choroba
in thread $var{el} += 1 vs $var{el} = $var{el} + 1 by banesong

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