Gross domestic product (GDP): Measuring economic output

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How does economic output measure up?

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Investors juggle dozens of monthly data releases, but gross domestic product (GDP) is “king of the hill” in terms of measuring economic health. At a high level, GDP reports tell you if the U.S. economy is expanding or contracting and why. Companies and the Federal Reserve often base decisions on GDP trends, so as an investor, you should understand the data and be ready to adjust your portfolio accordingly.

Measuring GDP is like taking someone’s temperature. It’s a single number that tells you if things are generally going well or if there’s some underlying problem or set of problems sending things off track. That said, GDP has advantages over a thermometer’s single data point.

If the economy is laid up in bed, GDP provides insight into exactly what’s wrong and why, including whether it’s an isolated infection or a full-on health emergency. Unlike other economic reports, GDP collects and computes numbers from all across the economy—not just from a single isolated section—and spits back a diagnosis.

Gross domestic product measures the total value of all goods and services produced in the United States. Tracking GDP over time can provide a sense of long-term trends in the economy.

GDP isn’t just some esoteric number for financial experts; it factors directly into your daily life. Suppose you take a trip to the grocery store. Everything you and the other shoppers buy gets measured in the GDP data.

But it goes beyond that. GDP also factors in the wages and benefits of the store’s employees, the money spent on utilities to keep the store warm in the winter and cool in the summer, the technology that helps the store’s corporate management run smoothly, the entire domestic supply chain (and its employees) that produced and transported goods to the store, and even the fuel you bought and used to get you to the store and back.

And that’s only a small fraction of what goes into GDP. If you look around, most of what you can see (or imagine) that once had a price tag somehow factored into GDP.

If you’ve ever taken a course in macroeconomics, you’ve no doubt seen this formula:

GDP="C" + I + G + (X–M)

Breaking it down, GDP is the sum, on a national scale, of:

If you think of all this in dollar terms and on a national scale, you’re looking at a colossal amount of money. According to the U.S. Bureau of Economic Analysis (BEA), as of the end of 2024. the U.S. GDP is $29.7 trillion.

Each GDP report provides a headline number telling you how much the economy grew or contracted year-over-year. This is measured by a percentage figure released after each quarter. Drilling down into the report, you can learn what factors drove the increase or decrease. Did the government spend more? Were corporations cutting back? It’s in there.

GDP reports, published by the BEA, are estimated on a quarterly and annual basis, although statistics are released each month.

Why each month? Because the BEA calculates GDP three times consecutively each quarter (advance, second, and third estimate). This way, data that’s still coming in can be incorporated into the estimates, making each quarterly report more accurate.

GDP data can help businesses shape their strategies. The Federal Reserve uses GDP data to help guide its monetary policy (whether it’s going to raise, lower, or hold steady the Fed funds rate). GDP can also help investors make smarter decisions about where to put their money.

Quarterly GDP releases don’t often elicit a strong response from the markets. That’s partly because they highlight economic decisions by consumers and companies that already took place—looking backward rather than forward. This makes GDP a lagging indicator.

If a GDP release reflects what analysts and investors have already estimated, the market might not react much. Typically, GDP doesn’t surprise the market because analysts and investors keep an eye on all the data that goes into GDP. If things are going well or badly, it’s often easy to tell long before the GDP comes out.

On rare occasions when GDP data is a surprise, you may see a strong market reaction as investors reposition their portfolios based on the new information and its implied outlook. Weak GDP tends to send the prices of bonds and other fixed-income securities higher and the stock market lower. The opposite is true when GDP is strong.

What’s weak and strong? It depends. For many years in the 1980s and 1990s, annual GDP growth of 4% or higher was common. After 2000, U.S. GDP growth often struggled to reach 3%. In a recession, GDP is usually negative. Generally, 3% GDP growth is considered relatively strong, but anything under 2% is seen as soft.

When the economy is expanding, consumer demand is usually high, business profits are booming, and investors are more willing to invest with a “risk-on” mindset. Consequently, stock prices tend to rise.

As an investor in a rising GDP environment, your portfolio might benefit from loading up on high-growth stocks rather than bonds. You’re taking on more risk in pursuit of a higher return. You’ll also have to decide on the size of your stock positions, whether to buy more or less, for how long, and in which sectors of the broader market.

When GDP signals economic contraction, it means consumers are saving more than they’re spending. As a result, business profits decline. Share prices tend to sink, and investors typically rotate from stocks to historically more stable investments like bonds and other fixed-income securities. If they do stay in stocks, they might gravitate toward defensive sectors like consumer staples that don’t tend to get blown around so much by prevailing economic winds. The idea is that no matter which way GDP is trending, people still need food, shelter, and health care.

To better understand GDP’s impact on your investing, it’s helpful to learn about economic cycles (also called “business cycles”) and which sectors tend to perform better or worse in each part of the cycle. Economic cycles are often driven by GDP.

Is there a way to monitor GDP in real time, making it more actionable by reducing the lag time of the quarterly data? Officially, no; unofficially, yes. The Federal Reserve Banks of Atlanta and New York offer their own respective tallies of GDP factors.

The Atlanta Fed’s GDPNow is a forecasting model with estimates similar to one used by the BEA. The New York Fed’s Nowcasting Report is another model that attempts to estimate GDP growth using a wide range of macroeconomic data as it unfolds. Each is updated regularly throughout the quarter between official GDP reports.

Although neither of these reports is made in direct partnership with the BEA, they’re among the closest estimates you’ll find to the official GDP reports. You can follow these GDP “trackers” to help make smarter portfolio allocation decisions well before the BEA’s official publications.

GDP is a lagging scorecard of economic health. Although it may provide the most comprehensive picture of the state of the economy, it’s not the most forward-looking of economic indicators. Furthermore, the best way to read GDP is in its relation to past GDP figures. Only then can you assess an economy’s direction (toward growth or decline).

In other words, GDP may not help you anticipate future economic trends, but it can help you confirm (or disprove) the data from other reports. It’s important to combine GDP data with other economic indicators such as employment data, consumer sentiment, and inflation figures. You may also want to follow GDPNow and the Nowcasting Report to see how GDP may be shaping up before the next official release.