An Introduction to the IPUMS Extract API for Microdata

By Renae Rodgers

Have you heard the news?! The IPUMS Extract API now supports microdata! For users who have been clamoring for this feature for some time, feel free to skip to the final section for resources to get started. For our users who haven’t been awaiting this announcement with bated breath, and who may be saying to themselves, “ok…great…but…”


This blog post will give a brief introduction to APIs, give some examples of ways to use the IPUMS Extract API in your workflow, and share some more in-depth resources.

What is an API?

API stands for Application Programming Interface. An API is an intermediate layer between a user and a server that allows the user to interact programmatically with another program or a service. First, the user’s program talks to the API – this is known as making an API call or a request. The API, in turn, talks to the server, translating the user’s request into something the server can understand. The server returns the requested information to the API, and the API then returns that information to the user. For example, Google Maps has an API that allows developers to request and retrieve information from Google Maps from within their applications, without needing to go through a web interface.

At this point you may be thinking, “great, now I have a general idea of what an API is, but I am not a software developer so… thanks anyway.”


The IPUMS Extract API opens up many possibilities for easing collaboration, and creating efficient workflows with only a few simple lines of code. Please read on!

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IPUMS International 2022 Data Release

By Jane Lyon Lee, IPUMS International

IPUMS International has added 7 new census samples and new labor force surveys including the first-time data release from the Slovak Republic and historical samples from Egypt 1848 and 1868. The other newly added samples extend pre-existing series. The growing IPUMSI labor force survey collection has expanded with the addition of quarterly surveys from Mexico (ENOE 2005-2020) and more data from Spain & Italy. See a summary of the full IPUMS collection on the IPUMSI samples page.

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How the COVID-19 Pandemic Impacted the 2020 ACS 1-year PUMS Data

By Danika Brockman and Megan Schouweiler

One of the highlights of the past IPUMS USA release was the 2020 ACS 1-year Public Use Microdata Sample (PUMS) file. Due to the effects of the COVID-19 pandemic on 2020 ACS data collection and data quality, the Census Bureau did not release the standard PUMS data. Instead, they released the 2020 ACS 1-year data with experimental weights designed to account for the impact of the COVID-19 pandemic on data quality. In this blog post, we discuss the impact of the COVID-19 pandemic on the 2020 ACS and the development of the experimental weights, and we provide some recommendations for using the 2020 ACS 1-year PUMS file.

Impact of the Covid-19 Pandemic on Data Collection and Data Quality and the Development of the Experimental Weights

The COVID-19 pandemic severely disrupted data collection for the 2020 ACS. All methods of data collection were either shut down or significantly reduced from March 2020 through the end of the year. Data collection for group quarters was particularly disrupted by the COVID-19 pandemic; in-person visits to group quarter facilities were suspended or greatly reduced from March 2020 through the end of the year, and telephone interviews were not conducted due to logistical constraints. Beyond the impacts to data collection methods, the 2020 ACS had significant variability across the 2020 data collection year in response rates for both housing units and group quarters, and had the lowest overall response rate in the history of the ACS1.

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