Data is possibly a spreadsheet.

use strict;
use warnings;
my ($B,$I,$K,$S);

while (<DATA>) {
  chomp;
  last unless ($_);
  ($B,$I,$K,$S) = (split /,/,$_)[1,8,10,18];
  if ($I == $B) {
    $K = abs($K);
  } elsif ($I == $S) {
    $K = -1 * abs($K);
  }
  print "$K\n";
}

__DATA__
0,2,0,0,0,0,0,0,2,0,1,0,0,0,0,0,0,0,3
0,2,0,0,0,0,0,0,3,0,1,0,0,0,0,0,0,0,3
0,2,0,0,0,0,0,0,4,0,-5.5,0,0,0,0,0,0,0,3
[download]

Output:

1
-1
-5.5
[download]

Update: $K = -1 instead of $K *= -1