There's an old grim joke about those who hold multiple jobs.
Comment: "Hey, did you hear the US economy created 100,000 new jobs last month?"
Response: "Yeah, I'm doing three of them."
Holding multiple jobs isn't always a bad thing: for example, a number of doctors technically have one job at a private practice and another when they work at a hospital. But in the past, it has been hard to find detailed or consistent evidence on multiple job-holders. For example, household survey data often asks about one's main job, not about all jobs.
Keith A. Bailey and James R. Spletzer of the US Census Bureau Have cracked this problem by finding a way to use data from the Longitudinal Employer-Household Dynamics (LEHD). The Census Bureau has published a readable short overview of their work in "Using Administrative Data, Census Bureau Can Now Track the Rise in Multiple Jobholders" (February 3, 2021). The full working September 2020 working paper, "A New Measure of Multiple Jobholding in the U.S. Economy," is at the Census Bureau website, too.
The LEHD is based on data that the government was already collecting for other purposes: for example, data on employment that was being collected for the unemployment insurance program, or data from the Quarterly Census of Employment and Wages, and other sources However, this data was often collected for administrative purposes (like running unemployment insurance), and so the task of the LEHD is to pull together data from a variety of sources into an anonymized dataset that can be used by researchers.
Here are some basic findings from Bailey and Spletzer: About 7-8% of the workforce holds multiple jobs, with the share tending to rise when the economy is going well and fall during recessions. The share of people holding multiple jobs seems to be edging up over time, but slowly.
Some other patterns:
Women hold multiple jobs at a higher rate than men and the rate has increased in the last 20 years. In the first quarter of 2018, 9.1% of women and 6.6% of men were working more than one job. ...
[M]ost multiple jobs are clustered in a few industries. Here’s the percentage of second jobs by sector:
Full-quarter jobs are long-lasting, stable jobs that exist in the previous quarter, the current quarter and the following quarter. Multiple jobholders earn less. ... Why do persons with multiple jobs earn less, on average, from all jobs compared to persons with only one long-lasting, stable job? Our working paper shows that this earnings differential is due to age, gender and the industries that employ multiple jobholders. ...
On average, earnings on all multiple jobs account for 28% of a multiple jobholder’s total earnings ($3,780 divided by $13,550). ...
One of the most striking findings is that the share of total earnings that come from multiple jobholding is above 25% for every percentile.
A basic lesson here is that those with multiple jobs depend fairly heavily on those jobs, in the sense that a quarter or more of their income comes from the additional jobs. One suspects that many of these workers are putting in a lot of total hours, but with limited access to many of the common benefits of full-time jobs like paid vacation, employer-provided health insurance, and contributions to a retirement account.
A version of this article first appeared on Conversable Economist.
Timothy Taylor is an American economist. He is managing editor of the Journal of Economic Perspectives, a quarterly academic journal produced at Macalester College and published by the American Economic Association. Taylor received his Bachelor of Arts degree from Haverford College and a master's degree in economics from Stanford University. At Stanford, he was winner of the award for excellent teaching in a large class (more than 30 students) given by the Associated Students of Stanford University. At Minnesota, he was named a Distinguished Lecturer by the Department of Economics and voted Teacher of the Year by the master's degree students at the Hubert H. Humphrey Institute of Public Affairs. Taylor has been a guest speaker for groups of teachers of high school economics, visiting diplomats from eastern Europe, talk-radio shows, and community groups. From 1989 to 1997, Professor Taylor wrote an economics opinion column for the San Jose Mercury-News. He has published multiple lectures on economics through The Teaching Company. With Rudolph Penner and Isabel Sawhill, he is co-author of Updating America's Social Contract (2000), whose first chapter provided an early radical centrist perspective, "An Agenda for the Radical Middle". Taylor is also the author of The Instant Economist: Everything You Need to Know About How the Economy Works, published by the Penguin Group in 2012. The fourth edition of Taylor's Principles of Economics textbook was published by Textbook Media in 2017.