As far as managing the structure of the data goes, it looks like this should be sufficient:

#! /usr/bin/perl -w
use strict;
use Data::Dumper;

my %data;

while ( <DATA> ) {
    chomp;
    my ( $begin, $end, $tag, @vals ) = split /[-,:]/;
    push @{$data{$begin}{$tag}{end_vals}}, $end;
    push @{$data{$begin}{$tag}{vals}}, @vals;
}

print Dumper \%data;

__DATA__
100-233,MA,150:250
100-344,MA,350:
200-400,ER,
200-300,ER,576
[download]

I'll leave the formatting up to you. :-)