Direct costs include all attributable expenses except interest, depreciation and amortization, taxes and fair value changes and are  primarily related to cost of sales and compensation. The following table lists direct costs for 2013 and 2012 by nature: Other income includes a $525 million gain on the settlement of a long-dated interest rate swap contract. In August 2013,  the company paid $905 million to terminate the contract, which had accrued to $1,440 million in our Consolidated Financial  Statements at the time of settlement. The gain was determined based on the difference between the accrued liability immediately  prior to termination and the termination payment amount, adjusted for associated transaction costs and recorded in our corporate  activities segment.  Fair value changes recorded in net income represent gains or losses arising from changes in the fair value of assets and liabilities,  including derivative financial instruments, accounted for using the fair value method and are comprised of the following: The company’s activities expose it to a variety of financial risks, including market risk (i.e., currency risk, interest rate risk, and  other price risk), credit risk and liquidity risk. The company and its subsidiaries selectively use derivative financial instruments  principally to manage these risks. The aggregate notional amount of the company’s derivative positions at December 31, 2013 and 2012 is as follows: 138 BROOKFIELD ASSET MANAGEMENT  23.  DIRECT COSTS 24.  OTHER INCOME 25.  FAIR VALUE CHANGES 26.  DERIVATIVE FINANCIAL INSTRUMENTS YEARS ENDED DECEMBER 31 (MILLIONS) 2013 2012 Cost of sales  $ 10,416 $ 10,846 Compensation  1,125 1,018 Selling, general and administrative expenses  975 534 Property taxes, sales taxes and other  1,412 1,563 $ 13,928 $ 13,961 YEARS ENDED DECEMBER 31 (MILLIONS) 2013 2012 Investment properties  $ 1,031 $ 1,276 Power contracts  (134) 9 Interest rate and inflation contracts  10 (81) Private equity and residential development  (127) (119) Sustainable resources  19 135 Redeemable units  (20) (11) Other  (116) (56) $ 663 $ 1,153 (MILLIONS) Note Dec. 31, 2013 Dec. 31, 2012 Foreign exchange  (a) $ 11,194 $ 6,159 Interest rates  (b) 16,757 18,671 Credit default swaps  (c) 800 865 Equity derivatives  (d) 1,633 1,112 Commodity instruments (e) Dec. 31, 2013 Dec. 31, 2012 Energy (GWh)  102,331 73,902 Natural gas (MMBtu – 000’s)  12,764 41,922