Consolidated  Notes to the  Financial  Statements 138 Note 53 – Financial instruments (continued) (k) Fair value measurements The following table provides an analysis of financial instruments that are measured subsequent to initial recognition at fair value, grouped  into Levels 1 to 3 based on the degree to which the fair value is observable. > Level 3 fair value measurements are those derived from valuation techniques that include inputs for the asset or liability that are not  based on observable market data (unobservable inputs). > Level 2 fair value measurements are those derived from inputs other than quoted prices included within Level 1 that are observable  for the asset or liability, either directly (as prices) or indirectly (derived from prices). > Level 1 fair value measurements are those derived from quoted prices (unadjusted) in active markets for identical assets or liabilities. There were no material transfers between Level 1 and Level 2 during the year. The fair value of financial instruments with standard terms and conditions and traded in active liquid markets (such as publicly traded  derivatives and listed equity investments) is determined with reference to quoted market prices at the end of the reporting period. These  instruments are included in Level 1. Level 1 $m Level 2 $m Level 3 $m Total $m 2012 Financial assets Available-for-sale financial assets  – Shares in listed entities 0.3  –  –  0.3  Derivative financial instruments – Interest rate swap contracts – cash flow hedges –  0.1  –  0.1  – Energy derivatives – cash flow hedges –  130.5  419.8  550.3  – Energy derivatives – economic hedges 8.2  50.5  –  58.7  8.5  181.1  419.8  609.4  Financial liabilities Derivative financial instruments – Cross currency swap contracts – cash flow and fair value hedges –  (20.4) –  (20.4) – Interest rate swap contracts – cash flow hedges –  (194.0) –  (194.0) – Forward foreign exchange contracts – cash flow hedges –  (10.6) –  (10.6) – Energy derivatives – cash flow hedges –  (32.3) –  (32.3) – Energy derivatives – economic hedges (18.3) (276.9) (72.9) (368.1) (18.3) (534.2) (72.9) (625.4) 2011 Financial assets Available-for-sale financial assets  – Shares in listed entities 0.3  –  –  0.3  Derivative financial instruments – Forward foreign exchange contracts – cash flow hedges –  0.5  –  0.5  – Energy derivatives – cash flow hedges –  67.9  6.0  73.9  – Energy derivatives – economic hedges 9.1  106.0  107.1  222.2  9.4  174.4  113.1  296.9  Financial liabilities Derivative financial instruments – Cross currency swap contracts – cash flow and fair value hedges –  (85.9) –  (85.9) – Interest rate swap contracts – cash flow hedges –  (4.4) –  (4.4) – Forward foreign exchange contracts – cash flow hedges –  (58.7) –  (58.7) – Energy derivatives – cash flow hedges –  (124.6) (1.7) (126.3) – Energy derivatives – economic hedges (29.4) (136.9) (93.2) (259.5) (29.4) (410.5) (94.9) (534.8)