public function compareTo(MoneyInterface $money)
    {
        if ($this->currency !== $money->getCurrency()) {
            throw new CurrencyMismatchException('Operations between different currencies are not supported.');
        }

        if ($this->amount == $money->getAmount()) {
            return 0;
        }

        return $this->amount < $money->getAmount() ? -1 : 1;
    }