There is no risk of this arbitrage. Range and once the two currencies yield, the yield of arbitrage mechanism will make two currencies are equal, that is, different interest rates in the currency of the country there is inherently a trend towards an equalization and trend, it is the interest rate index key aspects of the impact of foreign exchange to, also is our interpretation and grasp the key interest rate index. Data released by the American petroleum institute (API) showed that U.S. crude oil inventories fell 5.2 million barrels in the week ended Dec. 15, down from an expected 35.18 million barrels. Refinery inventories fell more than expected, while gasoline inventories rose, but were less than expected. The overall API data is good and good for oil prices. "Manufacturing companies with complex and lengthy international supply chains, such as the automotive industry, could also face significant challenges. These developments could also have a significant impact on productivity growth. "