Recognition of the ordinary usage prevailing between bankers and their customers results in agreements between bankers and their customers being construed as authorizing bankers to compound interest due to them from time to time (see, for example, National Bank of Greece S.A. v Pinios Shipping Co. No. 1 [1990] 1 AC 637; see also Jageev Pty Limited v State Bank of New South Wales (unreported, Supreme Court of NSW, Sperling J, 26 March 1996)).
The authorities make it plain that the usage prevailing between bankers and customers whereby unpaid interest is compounded with the principal due to the banker is based upon a recognition of entitlement in the banker to such interest as it accrues due. In Reddie v Williamson (1863) 1 Macph 228 at 237 the Lord Justice-Clerk said:
"The privilege of a banker to balance the account at the end of the year, and accumulate the interest with the principal, is founded on this plain ground of equity, that the interest ought then to be paid, and, because it is not paid, the debtor becomes thenceforth debtor in the amount, as a principal sum itself bearing interest."
In Paton v Inland Revenue Commissioners [1938] AC 341 at 349-350, Lord Atkin cited with approval the above passage from Reddie v Williamson and at 357 Lord Macmillan said:
"... it was held in Eaton v Bell [5 B & Ald 34], that bankers who, with the knowledge of and without objection by their customers, debited them with interest with half-yearly rests in accordance with their general practice, did not offend against the usury laws. This method of dealing with loan
accounts, which became common form among bankers, survived the abolition of the usury laws and is well established as the ordinary usage prevailing between bankers and customers who borrow from them and do not pay the interest as it accrues."
In this case it cannot be suggested that the applicants respectively had an entitlement to be paid interest under the deeds pending the determination of the proceedings. The obligation of the Civil Aviation Authority under the deeds is, in the events which have happened, to pay the sums respectively specified therein as the "Moneys", together with interest at the specified rate calculated from the date of the deed, within seven days of the day a final order is entered in these proceedings. In this sense, at least, in my view, the relationship between the parties under the deeds is readily distinguishable from the relationship between a banker and a customer, or indeed, from the ordinary relationship between a lender and a borrower.
In Consolidated Fertilizers Ltd v Commissioner of Taxation (1992) 36 FCR 1, Cooper J was required to determine whether the interest contemplated by ss9(1) and 10 of the Taxation (Interest on Overpayments) Act 1983 (Cth) was simple or compound interest. The rules of statutory construction are different from those which govern the interpretation of contracts. However, it is of interest to note that in reaching the conclusion that simple interest was contemplated by the section, his Honour had regard to the following factors:
(a) the only sum upon which the statute authorized interest to be calculated was the amount of the overpayment of taxation (i.e. there was no statutory provision for interest to be calculated on interest);
(b) the statute, except in limited circumstances, provided for only one calculation of the amount to be paid to the taxpayer; and
(c) the statute did not provide for rest periods so as to allow the calculation of compound interest; his Honour expressly declined to imply annual rest periods from a rate of interest expressed as a per annum rate.
I agree with his Honour's conclusion that a reference to an annual rate of interest is not of itself sufficient to justify an implication of annual rest periods for the calculation of compound interest. The factors listed above to which his Honour had regard in construing the Taxation (Interest on Overpayment) Act are all factors which can be identified in the deeds. They are factors which I consider it appropriate to take into account in determining the meaning reasonably to be ascribed to the phrase "with interest at the rate of 7.5% per annum on such amount" appearing in cl 3 of the deeds. They are, in my view, factors of greater weight than those upon which the applicants place reliance which, as it seems to me, fail to come to terms with the actual wording of cl 3(a) of the deeds.
Having regard to the natural and ordinary meaning of the language of cl 3 of the deeds read in the light of the deeds as a whole, and having regard to the purpose that the deeds were intended to serve, I find that the phrase "with interest at the rate of 7.5% per annum on such amount" appearing in cl 3 of the deeds creates an entitlement to simple interest and does not create an entitlement to compound interest. I have reached this conclusion without reference to any presumption that unless there is a clear agreement to pay compound interest, interest is to be taken to be simple interest (see Bakker v Chambri Pty Ltd (1986) 4 BPR 9234 at 9236). I do not consider it to be necessary for me in this case to reach a concluded view on the present status and reach of the presumption referred to by Young J in Bakker v Chambri Pty Ltd.
The other main issue of controversy between the parties relates to certain reserved costs. It is contended on behalf of the respondent that the orders for costs in favour of the applicants should except certain reserved costs, and that the applicants should be ordered to pay the respondent's costs of -
(a) the applicants' summons for the reservation of certain questions for consideration by a Full Court of the High Court; and
(b) two motions heard by Neaves J which were subject of orders made by his Honour on 18 March 1994.