在任何市場中，美元指數 (USDX) 都是重要的分析工具。USDX實際是一種期貨合約，這表示如果你有一個期貨交易賬戶，你可以像交易玉米、原油、黃金以及貨幣期貨合約一樣交易它。USDX除了被用於交易，還被大多數交易者視為分析美元總體強弱的工具。
USDX是將美元 (USD) 同其他國家的一籃子貨幣進行對比。這個籃子代表了主要貨幣的加權平均數的最大自由浮動量。這個貨幣籃子包含歐元、日元、英鎊、加元、瑞典克朗、瑞士法郎。美指會對上述每一個貨幣進行加權，其中歐元的比重最大。
歐元在美指中占比約有一半，投資者們通常觀察的是歐元/美元期貨合約的圖表。現貨外匯交易者很容易就能發現USDX和歐元/美元現貨貨幣對的走勢幾乎是完全相反的。但USDX因為包含六種貨幣對，能夠更好地衡量美元的強度，比單一的歐元/美元貨幣對更加有效。
USDX最初建立於1973年，起始價值為100。如果USDX跌至100以下，說明美元的價值低於1973年的水平；如果漲至100以上，說明美元強於1973年的水平。當前的USDX在82附近徘徊，說明美元較初始價值下跌了18%。但美元並非自1973年起一蹶不振，在2001年至2002年間，USDX較初始價值上漲了20%。
USDX在債券、貨幣及黃金市場中尤為重要。舉例來講，美元強勢往往會伴隨著金價下跌，這意味著即使交易員沒有直接交易美元，也會對美元抱有極大的興趣。在經濟形勢動蕩的時期，美元常被用作避險工具，美元價格會增加，而債券收益會減少。
如果你對USDX交易感興趣，你有兩個選擇。其一，開設一個期貨賬戶，交易美指的期權和期貨。其二，你可以交易追蹤USDX的ETF。
Trading the Dollar With USDX
The US dollar index (USDX) is an important analytical tool for traders in just about any market. The USDX is actually a futures contract which means that if you have a futures trading account you could trade this instrument like corn, oil, gold or currency futures contracts. However rather than trading the USDX most retail traders use it as way to analyze the relative strength or weakness of the US Dollar in general.
The USDX compares the US dollar (USD) against a basket of other world currencies. This basket represents most of the largest free floating, major currencies in the world on a weighted average basis. The currencies included are the euro, yen, British pound, Canadian dollar, Swedish krona and Swiss franc. Each of these currencies are given a weight within the index with the largest weight given to the euro.
The euro is typically half the total weight included in the average the chart for the USDX and will often look like a chart of the USD/EUR futures contract. Spot forex traders will notice that the USDX is very similar to an inverse of the EUR/USD spot forex pair. However, because the USDX includes 6 different currencies it is a better measure of USD strength than any single currency pair including the EUR/USD.
The USDX was established in 1973 with a starting value of 100. That means that if the USDX is measuring less than 100 the USD has lost relative value compared to what it was worth in 1973 and if it is above 100 then the USD is stronger than it was in 1973. Currently the USDX is hovering around 82, which means that it is 18% weaker than its starting value. The dollar has not always been weaker than it was in 1973, the USDX showed a 20% improvement in value in the USD in 2001 and 2002.
The USDX is particularly useful for traders in the bond, currency and gold markets. For example, a strong USD is usually correlated with falling gold prices, which means that gold traders are very interested in a break out on the USDX even though they may not be trading the USD directly. Similarly, global crises often increase demand for the USD as investors seek a shelter from uncertainty. This will drive the value of the USD up and often bond yields will drop. These are just two examples of how the USDX is one more inter-market tool you can use for evaluating capital flows and finding new trading opportunities.
Charts for the USDX on the pairs analysis pages in the forex section of the Learning Markets website but if you are interested in trading the USDX you have two attractive alternatives. First, you can open a futures account. There are futures and options on futures available on the USDX that trade on the New York Board of Trade.
Second you can trade ETFs that track the USDX itself. PowerShares offers two ETF alternatives for trading the index.
本文翻譯由兄弟財經提供
文章來源：http://www.thelfb-forex.com/content.aspx?id=174.