3(1)In section 640 (maximum amount of deductions) the following table shall be substituted for the table in subsection (2) (maximum amount by reference to age)—
| 36 to 45 | 20 per cent. |
| 46 to 50 | 25 per cent. |
| 51 to 55 | 30 per cent. |
| 56 to 60 | 35 per cent. |
| 61 or more | 40 per cent. |
(2)This paragraph shall have effect for the year 1989-90 and subsequent years of assessment.