From perlfaq5: 
How can I output my numbers with commas added?

This one will do it for you:

  sub commify {
      local $_  = shift;
      1 while s/^([-+]?\d+)(\d{3})/$1,$2/;
      return $_;
  }

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In reply to Re: Re: Numbers with commas by TilRMan
in thread Numbers with commas by Anonymous Monk

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