31It is true that that provision refers to the normal case of contractual relations entered into directly between two contracting parties, which are modified subsequently. The fact remains, however, that the provision is an expression of the principle, emphasized above, that the position of taxable persons must be neutral. It follows therefore from that provision that, in order to ensure observance of the principle of neutrality, account should be taken, when calculating the taxable amount for VAT, of situations where a taxable person who, having no contractual relationship with the final consumer but being the first link in a chain of transactions which ends with the final consumer, grants the consumer a reduction through retailers or by direct repayment of the value of the coupons. Otherwise, the tax authorities would receive by way of VAT a sum greater than that actually paid by the final consumer, at the expense of the taxable person.