collateral that is permitted might become more or less expensive due to other extraneous market movements. Credit and funding risks still exist for collateralised trades but to a much lesser extent. Due to regulations set out in the Basel III Regulatory Frameworks trading interest rate derivatives commands a capital usage. Dependent upon their specific nature XCSs might command more capital usage and this can deviate with market movements. Thus capital risks are another concern for users. Reputation risks also exist. The mis-selling of swaps, over-exposure of municipalities to derivative contracts, and IBOR manipulation are examples of high-profile cases where trading interest rate swaps has led to a loss of reputation and fines by regulators. Hedging XCSs can be complicated and relies on numerical processes of well designed risk models to suggest reliable benchmark trades that mitigate all market risks. The other, aforementioned risks must be hedged using other systematic processes. Market-making The market-making of XCSs is an involved process involving multiple tasks; curve construction with reference to interbank markets, individual derivative contract pricing, risk management of credit, cash and capital. The cross disciplines required include quantitative analysis and mathematical expertise, disciplined and organized approach towards profits and losses, and coherent psychological and subjective assessment of financial market information and price-taker analysis. The time sensitive nature of markets also creates a pressurized environment. Many tools and techniques have been designed to improve efficiency of market-making in a drive to efficiency and consistency. Historical facts In the 1990s Goldman Sachs and other US banks offered Mexico, currency swaps and loans using Mexican oil reserves as collateral and as a means of payment. The collateral of Mexican oil was valued at per barrel. In May 2011, Charles Munger of Berkshire Hathaway Inc. accused international investment banks of facilitating market abuse by national governments. For example, "Goldman Sachs helped Greece raise of off- balance-sheet funding in 2002 through a currency swap, allowing the government to hide debt." Greece had previously succeeded in getting clearance to join the euro on 1 January 2001, in time for the physical launch in 2002, by faking its deficit figures. Currency swaps were originally conceived in the 1970s to circumvent foreign exchange controls in the United Kingdom. At that time, UK companies had to pay a premium to borrow in US Dollars. To avoid this, UK companies set up back-to-back loan agreements with US companies wishing to borrow Sterling.