This text, constituting Article 51 of the VAT Implementing Regulations, establishes the rules for the proportional deduction of input tax. It mandates that tax incurred on goods and services used for both taxable and exempt supplies must be apportioned. The default calculation method is a fraction based on the value of taxable supplies versus total supplies from the previous calendar year. The Article details provisions for newly registered persons, year-end adjustments, and applying to the Authority to use an alternative, more accurate deduction method. It also clarifies deductibility for input tax related to specific incidental activities.