The US economy has changed a lot in the last several decades.

Using Census data, we found 20 industries that used to have a lot of young adults in their workforces that now are dominated by older workers.

Several manufacturing and wholesale industries made the list.

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Blockbuster, Pogs, and the Teenage Mutant Ninja Turtles aren't the only things that had their time in the sun in the early '90s — jobs that were popular with young people back then are no longer drawing millennials.

We recently looked at what industries are currently dominated by millennials. To get a sense of how the US economy has changed since baby boomers and Gen Xers were young adults, we looked for once-popular jobs that have very few millennials employed today.

Read more: 37 jobs that could be decimated by 2026

Using data from the Minnesota Population Center's Integrated Public Use Microdata Series for the 1990 Census and 2017 American Community Survey, we found the share of the workforce aged 21 to 36 — how old millennials were in 2017, according to the Pew Research Center — in each year for 224 industry groups tracked by the Census Bureau.

The Pew Research Center provided definitions for generations, meaning that in 1990, plenty of baby boomers and Gen Xers were the same age older millennials were in 2017. The industries we're looking at were popular with those young adults in 1990, but had a much smaller share of similarly aged millennials in 2017.

As with broader trends in the economy as globalization and automation reshape the way Americans work, many of the industries that have seen a big drop in young-adult employment are in the manufacturing and wholesale trade sectors.

For each industry, we also included the average income among 21- to 36-year-olds working in that industry in 1990 and in 2017, adjusted for inflation.