while (my $line1 = <$file2>){ 
        
  chomp $line1; 
  
  # Item,Sink,Buffer,Cell,Slew,Path,Violation,Area
  my @f = split /,/, $line1 ; 
  my $item = $f[0];
  my $slew = $f[4];
  next if $item eq 'Item'; # skip header
        
  if (defined $file1Hash{$item}) {
    my $period = $file1Hash{$item};
    my $pc = sprintf "%.10f",100*$slew/$period unless ($period==0);
    print $outfile_1 join ',',$line1,$period,$pc."\n";        
  } 
}
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