$pi_sum = 0;
    $L_sum = 0;
    $differences_sum = 0;
    $coverage_sum = 0;
    for my $PAR1 (@PAR1) {
			
	    my @PAR1_info = split(/\t/, $PAR1);

	    $pi = $PAR1_info[0];
	    $pi_sum = $pi_sum + $pi;
	
	    $L = $PAR1_info[1];
	    $L_sum = $L_sum + $L;
	
	    $differences = $PAR1_info[2];
	    $differences_sum = $differences_sum + $differences; 
	
	    $coverage = $PAR1_info[3];
	    $coverage_sum = $coverage_sum + $coverage;
	

       	my $PAR1_diversity = (($pi_sum/$L_sum)/($differences_sum/$coverage_sum));
	}