Here's how I would approach it -- it cuts down on redundant code (doing X for three lines, and doing a very similar X for two lines):

until (eof FILE) {
  for my $count (3, 2) {
    my @set = map scalar <FILE>, 1 .. $count;
    my ($time, @totals);

    for (@set) {
      chomp;
      my @f = split /\t/;
      $time ||= shift @f;  # only want the FIRST time
      $totals[$_] += $f[$_] for 0 .. $#f;
    }

    print OUT join("\t", $time, map $_/$count, @totals), "\n";
  }
}
[download]

That's incomplete, as far as formatting the proper date and time, but it's a pretty good start.

_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a job (NYC-area)
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