The amount of the writing-down allowance to which a person is entitled for a chargeable period is 25% of the amount by which AQE exceeds TDV.

If the chargeable period is more or less than a year, the amount is proportionately increased or reduced.

If the trade has been carried on for part only of the chargeable period, the amount is proportionately reduced.

A person claiming a writing-down allowance may require the allowance to be reduced to a specified amount.

The amount of the balancing charge to which a person is liable for a chargeable period is the amount by which TDV exceeds AQE.

The amount of the balancing allowance to which a person is entitled for the final chargeable period is the amount by which AQE exceeds TDV.