Disclosure and presentation

Trade Receivables 
Trade receivables are carried at original invoice amount less an estimate made for 
doubtful receivables based on a review of all outstanding amounts at the year end. 
Bad debts are written off when identified. 
Investments 
Interests in listed and unlisted securities, other than controlled entities and associates 
in the consolidated financial statements, are recognized at cost and dividend revenue 
is recognized in the statement of financial performance when receivable. 
The principal amount of zero coupon bonds is calculated by discounting the cash 
flow associated with the ultimate redemption of the investment. The discount is 
amortized over the period to maturity. The discount rate is that implicit in the 
transaction. 
Borrowings 
Loans and debentures are carried at their principal amounts which represent the 
present value of future cash flows associated with servicing the debt. Interest is 
accrued over the period it becomes due and is recorded as part of other creditors.
On issue of convertible notes, the fair value of the liability component, being the 
obligation to make future payments of principal and interest to noteholders, is calculated 
using a market interest rate for an equivalent non-convertible note. The residual amount, 
representing the fair value of the conversion option, is included in equity as other equity 
securities with no recognition of any change in the value of the option in subsequent 
periods. The liability is included in borrowings and carried on an amortized cost basis 
with interest on the notes recognized as borrowing costs on an effective yield basis until 
the liability is extinguished on conversion or maturity of the notes.
Redeemable preference shares which provide for mandatory redemption or which are 
redeemable at the option of the holder are included in liabilities as they are, in substance, 
borrowings. Dividends payable on the shares are recognized in the statement of financial 
performance as interest and finance charges on an accruals basis.