39 The net amount of GS T recoverable from or payable to the taxation authority is included as part of receivables or payables in the balance sheet Cash fows are included in the Cash Flow S tatement on a net basis and the GS T component of cash fows arising from investing and fnancing activities which is recoverable from or payable to the taxation authority are classifed as operating cash fows Property plant equipment Plant and equipment is stated at cost less accumulated depreciation and any accumulated impairment losses The assets residual values useful lives and amortisation methods are reviewed and adjusted if appropriate at each fnancial year end Depreciation is calculated on a straight line basis over estimated useful life of the asset The depreciation rate used for plant and equipment is 7 5 33 pa Impairment Carrying values of plant and equipment are reviewed for impairment at each reporting date with recoverable amount being estimated when events or circumstances indicate that the carrying value may be impaired The recoverable amount of plant and equipment is the higher of fair value less costs to sell and value in use In assessing value in use the estimated future cash fows are discounted to their present value using a pretax discount rate that refects current mark et assessments of the time value of money and the risk s specifc to the asset For an asset that does not generate largely independent cash fows recoverable amount is determined for the cashgenerating unit to which the asset belongs unless the asset s value in use can be estimated to be close to its fair value Impairment e xists when the carrying value of an asset or cash generating units e x ceeds its estimated recoverable amount The asset or cashgenerating unit is then written down to its recoverable amount For plant and equipment impairment losses are recognised in the income statement in the cost of sales line item However because land and buildings are measured at revalued amounts impairment losses on land and buildings are treated as a revaluation decrement T rade and other payables T rade payables and other payables are carried at amortised cost due to their short term nature and they are not discounted They represent liabilities for goods and services provided to the entity prior to the end of the fnancial year that are unpaid and arise when the entity becomes obliged to mak e future payments in respect of the purchase of these goods and services The amounts are unsecured and are usually paid within 30 days of recognition Employee leave entitlements Liabilities for wages and salaries including nonmonetary benefts annual leave and accumulating sick leave e xpected to be settled within 12 months of the reporting date are recognised in other payables in respect of employee s services up to the reporting date OPERA TIONAL AND FINANCIAL REPOR T NO TES T O AND FORMING P AR T OF THE A CCOUNT S AMEC R eport 2018