#!/usr/bin/env perl
#       $Id: 1199549.pl,v 1.2 2017/09/17 13:01:45 karl Exp karl $
# http://perlmonks.org/?node_id=1199549

use strict;
use warnings;
use Data::Dump;
use List::Util qw(sum);
use feature qw (say);

my $result = '2017-08-01 20MICRONS 37744                                                                          
2016-08-01 20MICRONS 25966                                                                                        
2016-04-20 20MICRONS 30807                                                                                        
2016-04-01 20MICRONS 32780';

my @numbers = grep { /\d{5}/ } split /[\n,\s]/, $result;

say sum (@numbers) / scalar @numbers;

__END__