Measuring Local Participation in Global Markets: Introducing the PLEXT Dataset 

By Christoph E. Boehm

What are the effects of the recent increase in Chinese import tariffs on exports from Texas? How do these tariffs impact workers in cities like Austin, Dallas, or Houston? And is there hope that the goods once destined for Chinese markets can instead be sold to other foreign trading partners with whom Texan firms already maintain established relationships? 

These are the kinds of questions that, until recently, were challenging to answer with the U.S. trade data available. The problem lies in the fact that data on U.S. exports and imports is collected at the firm level. Because most exporting firms are large and often operate plants across multiple regions of the country, it is difficult to determine where the production of exported goods takes place and where the workers involved are employed. This lack of geographic detail leaves policymakers in the dark about where the benefits of trade accrue and where the risks associated with fluctuations in foreign demand are concentrated. 

Recent work by Boehm, Flaaen, Pandalai-Nayar, and Schlupp aims to address this shortcoming. The researchers assembled a new dataset that makes it possible to accurately answer questions like those raised above. The idea behind this data resource—available with approved proposals through Census Research Data Centres—is to combine existing firm-level trade data with additional information on where firms operate plants, which products those plants produce, as well as related details, thereby allowing trade transactions to be linked to individual plants within each firm where the product being exported was likely produced. The result is a new dataset that reports trade transactions—including export values, product codes, destination countries, quantity measures, and more—at the plant level for the first time. 

This dataset, called the PLEXT data (for plant-level export transactions), also enables measurement of exports at various geographic levels, since plants have address information. For example, one can aggregate exports from all plants located in a given ZIP code, county, commuting zone, or state. As a result, the dataset can be used to answer questions of the sort raised above, for instance, how workers in Austin, Dallas, or Houston were affected by tariff changes. 

The authors also examine the properties of the new data. A striking finding they document is that exports in the United States are extremely concentrated geographically (see Figure 1, Figure 5 in the paper). In Texas, for example, more than 96 percent of exports in 2021 came from just 10 percent of counties. This pattern contrasts with the distribution of manufacturing sales and employment, which are also geographically concentrated but to a lesser degree. In Texas, the top 10 percent of counties account for roughly 85 percent of manufacturing sales and about 82 percent of manufacturing employment. 

Figure 1: Variation in concentration of employment, sales and exports of establishments for selected states 

This high degree of concentration implies that certain areas of the United States benefit enormously from access to foreign markets. For example, exports per worker in the combined metropolitan areas of El Paso, TX, and Las Cruces, NM, exceeded 35,000 dollars to Mexico alone—an indication of the substantial gains these regions derive from access to the Mexican market. While geographic proximity helps explain this particular case, exports per worker to other countries are also significant in various parts of the U.S. The combined metro areas of Beaumont–Port Arthur, TX, and Lake Charles, LA, for instance, exported more than 14,000 dollars per worker to China. These regions therefore benefit greatly from access to global markets, but the flip side is that they are also highly exposed to increases in foreign tariffs (see Figure 2, which is Figure 3 in the paper). 

Figure 2: Exposure of select Metropolitan Statistical Areas to China, Mexico and Canada through exports 

To illustrate one concrete application of the PLEXT data, the authors analyze the connection between local area exporting and employment during a specific episode of large swings in foreign demand and trade flows.  During the period of the Great Trade Collapse, which took place between 2007 and 2009, U.S. imports and exports fell by roughly 20 percent—a decline far larger than that of overall economic activity. The authors show that U.S. counties more exposed to foreign demand shocks experienced larger reductions in employment, payroll, and wages. This result quantifies how the positive local benefits of access to foreign markets are coupled with vulnerability to swings in foreign demand. The authors also demonstrate that common methods of attempting to infer local exports without detailed data such as the PLEXT data—for instance, by using product-level export data combined with local industry employment shares—cannot accurately reproduce directly measured local-area exports. 

The availability of the PLEXT data opens new avenues for analyzing trade patterns and their role in the U.S. economy. The researchers expect the dataset to be especially useful for research questions that require export data at the local level. How much do individual cities or regions benefit from access to foreign markets? How vulnerable are they to policies such as foreign tariffs? Are local export-promotion programs effective, and if so, how do they work? In addition, the PLEXT data substantially improves the accuracy of plant-level analyses. Researchers can now more precisely examine how many plants export (Answer: More than previously thought, see Boehm, Flaaen, and Pandalai-Nayar, 2023) and how their exporting relationships with foreign partner countries evolve over time. The authors look forward to future research that uses this dataset to answer these and many other important questions. 

References: 

Christoph Boehm, Aaron Flaaen, Nitya Pandalai-Nayar, and Jan Schlupp, “The Local-Area Incidence of Exporting,” NBER Working Paper 34508 (2025) 

Boehm, Christoph, Aaron Flaaen, and Nitya Pandalai-Nayar. 2023. “New Measurement of Export Participation in US Manufacturing.” AEA Papers and Proceedings 113: 93–98