my $pvalue = -1;
        foreach (@{$Statistics::ChiSquare::chitable[$degrees_of_freedom]}) {
                if ($chisquare < $_) {
                    $pvalue = $Statistics::ChiSquare::chilevels[$degrees_of_freedom]->[$i+1];
                    last
                }
                $i++;
        }
        $pvalue = (@{$Statistics::ChiSquare::chilevels[$degrees_of_freedom]})[-1] unless $pvalue > -1;
        $pvalue /= 100; # 0-1 e.g. 5% -> 0.05