So Big?

USA Today lists the University of California as the largest employer in the state with over 227,000 employees.* But this figure is a bit misleading. A number of other states shown have their public universities listed as number 1 in the same article, as you can see for Colorado on the same chart (below).

On a full-time equivalent (FTE) basis, UC has something over 109,000 employees, which puts it behind the State of California (other than higher ed) with about twice that total.** UC (like other public universities) use many part-timers, including student TAs and RAs, and part-time teaching staff. Public universities with hospitals - such as UC - use many part-time personnel for that function. (Hospital chains show up as the largest employer in some of the states in the USA Today article.)

Of course, part-timers are used by other public and private employers. But universities are especially intensive in their usage.

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*https://www.usatoday.com/story/money/business/2019/03/30/largest-employer-each-state-walmart-top-us-amazon-second/39236965/
**http://ebudget.ca.gov/2019-20/pdf/BudgetSummary/BS_SCH4.pdf