Untested: 
my %data;
while (<DATA>) {
    next if /^ID/ || /^\s$/;
    my ($id, $value) = split /,/;
    $data{$id}[0] += $value;
    $data{$id}[1] ++;
}
my %avg;
while (my ($id, $info) = each %data) {
    $avg{$id} = $$info[0] / $$info [1];
}

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In reply to Re: get the average of hash values? by JavaFan
in thread get the average of hash values? by luckysing

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