One possible way in perl: 
use strict;
use warnings;

my %ips;

# Deal with the column headers
my $cols = <>;
chomp ($cols);
my @cols = split(',',$cols);
print "$cols[0],$cols[2],$cols[3]\n";

while (<>) {
   my ($address, undef, $size, $free) = split(',');
   $ips{$address}{'size'} += $size;
   $ips{$address}{'free'} += $free;
}

# Note that the order of the lines in the output may not reflect
# the order of the addresses in the input file.
for my $address(sort keys %ips) {
   print "$address,$ips{$address}{'size'},$ips{$address}{'free'}\n";
}

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In reply to Re: Combine data in table by AReed
in thread Combine data in table by DrAxeman

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