public static function getDefaultFractionDigits($currencyCode)
    {
        $defaultFractionDigits = static::getCurrencyData($currencyCode)['default_fraction_digits'];
        if (!is_int($defaultFractionDigits)) {
            throw new UnexpectedValueException(sprintf(
                'The currency default fraction digits value must be an integer; "%s" given',
                is_object($defaultFractionDigits) ? get_class($defaultFractionDigits) : gettype($defaultFractionDigits)
            ));
        }
        if ($defaultFractionDigits < 0) {
            throw new UnexpectedValueException(sprintf(
                'The currency default fraction digits value must be greater than 0; "%s" given',
                $defaultFractionDigits
            ));
        }
        return $defaultFractionDigits;
    }