Form 318. Adjustment of the tax proportions of the settlement periods prior to the start of trading
Adjustments of refunded VAT payments in cases where taxpayers fell under any tax authority, local Foral administration or common tax agency in settlement periods before the start of trading, and under a different one in subsequent settlement periods; or when there are substantial variations in the proportion they pay in tax to the different Foral or common Tax Agencies in the aforementioned settlement periods.