#!/usr/bin/perl
use strict;
use warnings;

my %keys;

while(my $line=<DATA>)
{
  $keys{$1}++ if($line=~/,(.+?)$/);
}

while (my ($key,$val)= each(%keys))
{
  print "$key = $val\n";
}

__DATA__
Message = NPU$xy123/08Aug12344,ABS
Message = NPU$xy123/08Aug12344,ASR
Message = NPU$xy123/08Aug12344,ASR
Message = NPU$xy123/08Aug12344,ABS09
Message = NPU$xy123/08Aug12344,ACT12
Message = NPU$xy123/08Aug12344,ABS
Message = NPU$xy123/08Aug12344,ASR/88
Message = NPU$xy123/08Aug12344,ANTI
Message = NPU$xy123/08Aug12344,ANTI2