protected function _calculateRepeatTokenScore()
    {
        $score = 0;
        $repeats = 0;

        foreach ($this->_tokens as $tokenCount) {
            if ($tokenCount > 1) {
                $repeats += $tokenCount - 1;
            }
        }

        if ($repeats > 0) {
            $score -= (int) ($repeats / ($this->_length - $repeats)) + 1;
        }

        return $score;
    }