#!/usr/bin/perl -w

use strict;

$| = 1;

my $file = "test.txt";
my $maxsize = -s $file;
my $accsize = "0";
my $accperc = "0.0125";

print "    10%|    20%|    30%|    40%|    50%|    60%|    70%|    80%|    90%|   100%|\n";

open ( F, "<$file" ) or die $!;

while (<F>) {
  $accsize += length $_;
  if ( $accsize / $maxsize >= $accperc ) {
    print "#";
    $accperc += 0.0125;
  }
  # inserd your code here
}

print "\n";