Consider the graph above, which shows the U.S. trade balance. It looks like things are seriously heading south, with a deficit that’s ten times larger than it was 25 years ago. Is it really that bad? For one thing, the economy as a whole has grown significantly over this period, and prices have increased, too. To address these biases, we should divide the trade balance by our favorite nominal index, nominal GDP. The result is the graph below.

Now that the units are percentages of GDP, we can see that the deficit is five times as large as it was 25 years ago, not ten times. And it has actually improved since the previous recession, to a little more than three times its size, topping out at –4% of GDP. But wait, there’s more: International trade doesn’t pertain to goods alone; it also involves services. And here, the United States actually enjoys a surplus. So, if you redo the second graph with the trade balance for goods and services, you obtain the graph below:

Finally, we see that the current trade deficit is at about 3% of GDP. Is that a lot? Actually, a deficit isn’t necessarily bad. See a previous blog post on the topic.

How these graphs were created: For the first graph, simply search for “trade balance” and take the series that pertains only to goods. For the second graph, use the first and then go to the “Edit Graph” panel: From there, add “nominal GDP” and apply the formula a/b/10*12. (The idea is to divide by 1,000 to put both series into the same units and then multiply by 100 to obtain results in percentages, which reduces to simply dividing by 10. Multiplying by 12 changes the trade balance’s monthly frequency to an annual frequency, to match nominal GDP’s annual frequency.) For the the third graph, replace the trade balance for goods with the trade balance for goods and services.

Suggested by Christian Zimmermann.