Researchers are able to merge the state-level external data on this page, or from any source, with any UAS dataset without UAS assistance, using the included “statereside” (state of residence) variable. We will also consider requests to merge external files at the county or zip code level. Linkages at any level more granular than state may require provision of an additional data use agreement, and/or IRB review. Current external data sources include the following (last updated in July 2021):


The COVID Tracking Project

The COVID Tracking Project is a volunteer organization launched from The Atlantic and dedicated to collecting and publishing the data required to understand the COVID-19 outbreak in the United States. Every day, they collect data on COVID-19 testing and patient outcomes from all 50 states, 5 territories, and the District of Columbia. Their dataset is currently in use by national and local news organizations across the US and by research projects and agencies worldwide.


Researchers at the Boston University School of Public Health have compiled data on new and existing state health and economic policies relevant to responding to COVID-19. The database includes information on the dates of physical distancing policies, reopening policies, mask policies, unemployment policies, housing policies, SNAP benefits, and health insurance and telehealth policies. Policy sources are also publicly available to inform coding of additional policy details:

New York Times

The New York Times is releasing a series of data files with cumulative counts of coronavirus cases in the United States, at the state and county level, over time. They are compiling this time series data from state and local governments and health departments in an attempt to provide a complete record of the ongoing outbreak. Since late January, The Times has tracked cases of coronavirus in real time as they were identified after testing. Because of the widespread shortage of testing, however, the data is necessarily limited in the picture it presents of the outbreak.


IHME's COVID-19 projections were developed in response to requests from the University of Washington School of Medicine and other US hospital systems and state governments working to determine when COVID-19 would overwhelm their ability to care for patients. The forecasts show demand for hospital services, daily and cumulative deaths due to COVID-19, rates of infection and testing, and the impact of social distancing, organized by country and state

Opportunity Insights

The Opportunity Insights Economic Tracker combines anonymized data from leading private companies – from credit card processors to payroll firms – to provide a real-time picture of indicators such as employment rates, consumer spending, and job postings across counties, industries, and income groups.

In collaboration with their data partners, they are making this data freely available in order to assist in efforts to inform the public, policymakers, and researchers about the real-time state of the economy and the effects of COVID-19.

Included in our contextual data:



The unique identifier included in UAS data sets (uasid) may be used by researchers to link the Covid data set to other UAS data sets. The respondents’ state of residence (statereside) may be used to link UAS survey data to external data at the state level, including the external data sets available for download from this page. Merges at location levels more granular than state must be done by UAS staff, as we are not able to provide researchers with the key to linking uasids with location information.

UAS is able to merge the longitudinal Covid data with external data sets that are keyed with a FIPS data location. If merging the data does not add risk (an example is the 3-category census definition of urban/rural/mixed which is applied at the zip code level), the merge may easily be done without further requirements. Other data merges may require that you and your team fill out and return sensitive data addenda which must be counter-signed by your respective affiliated institutions. Depending on the nature of the data, documentation of IRB review may also be required.

To request a merge of the Covid data (or any UAS data) with external data at the county or zip code level, send a request to and attach the external file you wish to merge with UAS data, or a link to it. We will provide you with more information about any additional requirements, or costs that may be incurred, after evaluating the file, and your request.