Do you often hear the saying that to read the global market, you should look at the U.S. dollar index? There’s a reason these days that market analysts keep bringing it up. The U.S. dollar index isn’t just a simple exchange-rate indicator—it acts like a compass for gauging the direction of the global economy.

Let’s sort out exactly what the dollar index is first. In simple terms, the meaning of the U.S. dollar index is an indicator that quantifies how strong the U.S. dollar is versus six major currencies. It’s calculated based on exchange rates against six currencies: the euro, the yen, the pound, the Canadian dollar, the Swedish krona, and the Swiss franc. After the Bretton Woods system collapsed in 1973 and the floating exchange rate system began, the U.S. Federal Reserve introduced it. The baseline is 100. So if the dollar index is 120, it means the dollar’s value increased by 20% compared with the reference point at the 1973 baseline.

From an investment perspective, the meaning of the dollar index becomes even more interesting. What happens if the dollar strengthens? U.S. companies’ overseas earnings decrease, which negatively affects stock prices. On the other hand, commodity prices usually fall. That’s because international commodities are priced in dollars. When the dollar weakens, the opposite happens. It’s beneficial for U.S. export companies, but it increases the repayment burden of dollar-denominated debt for emerging markets.

Recently, I observed an interesting phenomenon. Usually, the gold price and the dollar index move in opposite directions, but this year, both dollar strength and gold prices rose at the same time. This is because as global economic uncertainty increases, overall demand for safe-haven assets rises. Understanding these kinds of phenomena can help you read the market’s hidden signals.

It also affects Korea’s stock market. When the dollar index rises, the Korean won weakens, which is good for export companies, but it can also lead to capital outflows from foreign investors. Conversely, when the dollar index falls, the won strengthens, making it more likely for foreign capital to flow in.

It’s also necessary to know the factors that influence movements in the dollar index. These include the U.S. economic growth rate, the Federal Reserve’s interest-rate policy, the level of inflation, the trade balance, and even political uncertainties such as global crises. During the COVID-19 pandemic or when geopolitical tensions intensified, we’ve seen a pattern in which the dollar is preferred as a safe-haven asset, causing the index to surge.

There are also several ways to gain exposure to the dollar index from an investment standpoint. You can invest indirectly through ETFs, or trade CME futures contracts. You can also trade currency pairs directly, such as EUR/USD or USD/JPY. Since each method has its pros and cons, you can choose the approach that best matches your investment style.

In the end, properly understanding the meaning of the dollar index is directly tied to your ability to read the global market as a whole. It’s not just a change in a number, but a signal that reflects the flow of the world economy—so you should observe and analyze it thoroughly before making investment decisions. Tracking the movement of various assets on Gate and looking at how they relate to changes in the dollar index can also be a good way to study.