Consolidated Santos Ltd 2004 2003 2004 2003 5. Profit from Ordinary Activities $million $million $million $million (a) Profit from ordinary activities before tax includes the following items Depreciation, depletion and amortisation: Depletion of exploration and development expenditure 344.3 333.8 116.5 119.7 Depreciation of plant and equipment 169.1 168.7 85.8 69.1 Depreciation of buildings 2.0 3.3 1.0 1.8 Future restoration costs 19.8 16.8 7.6 5.2 Amortisation of goodwill 4.5 9.0 – – 539.7 531.6 210.9 195.8 Charges to provisions: Doubtful debts (0.6) 0.2 (0.2) 0.1 Stock obsolescence 6.4 1.0 3.1 0.2 Employee entitlements and non-executive Directors’ retirement ben efits (0.3) 6.7 (0.3) 6.2 Operating lease rentals 42.2 45.6 21.4 22.5 Profit on disposal of non-current assets (52.4) (55.1) (297.7) (45.8) (Profit)/loss on disposal of controlled entities – (4.5) – 1.0 (b) Individually significant expenses/(gains) included in profit from  ordinary activities before income tax Insurance recovery (116.6) – (73.8) – Costs associated with Moomba liquids recovery plant fire included in cost of sales 17.5 – 11.9 – Profit on sale of oil and gas assets (43.9) – (298.4) – Write-down of exploration and development expenditure 22.1 59.7 4.6 6.1 Organisation restructure costs included in selling, general and administr ative expenses 21.6 – 21.6 – Accelerated depreciation – Heytesbury plant – 20.2 – – Profit on sale of investment in listed shares – (45.8) – (45.8) 6. Taxation Income tax attributable to profit from ordinary activities The prima facie income tax attributable to profit from ordinary activities differs from  income tax expense and is calculated as follows: Prima facie income tax at 30% (2003: 30%) 162.2 129.3 210.1 58.1 Tax effect of permanent and other differences which increase/(decrease) in come  tax expense: Non-deductible depletion, depreciation and amortisation 17.9 18.9 2.4 2.5 Write-down of investment in controlled entities – – – 12.2 Other 0.8 10.7 6.2 (14.5) Impact of the tax consolidation system Income tax expense allocated to wholly-owned controlled entities un der  tax funding agreement – – (64.0) (131.1) Income tax expense relating to transactions, events and balances of  wholly-owned controlled entities in the tax-consolidated group – – 60.5 138.5 Transactions within the tax-consolidated group: Dividends from controlled entities – – (75.5) – Non-deductible interest – – 14.2 – Profit on sale of oil and gas assets – – (76.8) – Tax benefit arising from reduced deferred tax balances upon enterin g into  Australian tax consolidation regime (20.0) (55.0) (20.0) (55.0) 160.9 103.9 57.1 10.7 Income tax comprises amounts set aside to: Provision for current income tax 143.1 144.7 120.9 126.1 Deferred tax liability 24.6 (16.5) 0.2 15.7 Deferred tax asset (1.6) 12.8 – – Foreign currency translation reserve (5.2) (37.1) – – Tax related receivable from wholly-owned controlled entities – – (64.0) (131.1) 160.9 103.9 57.1 10.7 Annual Report 2004 57