public function subtract(Money ...$subtrahends)
    {
        $amount = $this->amount;
        $calculator = $this->getCalculator();

        foreach ($subtrahends as $subtrahend) {
            $this->assertSameCurrency($subtrahend);

            $amount = $calculator->subtract($amount, $subtrahend->amount);
        }

        return new self($amount, $this->currency);
    }