#!/usr/bin/perl -w
       $infile = shift;
       $outfile = shift;
       
       open(IN, $infile) || die("Can't open input file $infile - $!");
       open(OUT, ">$outfile") || die("Can't open output file $outfile - $!");

       use strict;
       my $text;
       my @lines;

       while (<>) {
         push @lines;
         shift @lines if @lines > 10;
       }

       chomp(@lines);

       my @cols;
       my $total = 0;

       for (@lines) {
         @cols = split /:/;
         $total += $cols[3];
       }
       my $average = $total / (@lines || 1);
         # if no lines, avoid division by zero

       
 ***** error here*****      $text= "Average of column 3 for the last " ;#, scalar(@lines)," days: $average\n";
       


      print OUT "$text\n";
	
       close IN;
       close OUT ;