4(1)Where any amount of the chargeable deposits held by a deposit-taker at a material time consists of the credit balance or balances on one or more accounts which the deposit-taker treats as reducing or extinguishing the amount on which he is entitled to interest in respect of the debit balance or balances on one or more other accounts held with him at that time, that amount of chargeable deposits shall be treated as equal to its excess, if any, over that other amount.
(2)This paragraph applies only if the other account or accounts are denominated in sterling.