Article 18 of the KSA Income Tax Law outlines the rules for deducting expenses related to the repair or improvement of depreciable assets. As per paragraph (a), taxpayers are permitted to deduct these costs. However, paragraph (b) establishes a significant limitation: the deductible amount in any given year cannot exceed 4% of the asset group's value balance at the end of that year. Any expenditure surpassing this 4% threshold, as specified in paragraph (c), is not deductible in the current year but must be added to the balance of the asset group's value, effectively being capitalised.