The use of robots in U.S. workplaces has more than doubled since the Great Recession, but the impact has hit certain areas of the country — and segments of workers — more than others.
A recent report from The Century Foundation found Midwestern states such as Michigan, Ohio, Indiana, Illinois and Wisconsin saw the sharpest growth in robots being used in the workplace from 2009 to 2017, and these areas now have the highest levels of "robot intensity" in the country.
Robot intensity refers to the number of industrial robots per 1,000 human workers. The higher the number, the more robots there are in the workplace alongside humans.
Areas with the highest robot intensity are home to some of the of the biggest manufacturing industries in the country. Factory and production jobs have been proven to be highly susceptible to automation when robots and other automated machinery are able to do physical, routine work very quickly at high volume.
Nationwide, there are about 0.34 robots per every 1,000 human workers. But that number varies widely depending on the city.
These are the major cities and metro areas that have the highest concentration of robots compared to human workers in the workplace.
1. Los Angeles-Long Beach-Santa Ana, California
Robots per 1,000 workers: 6.91
2. Chicago-Naperville-Joliet, Illinois
Robots per 1,000 workers: 6.015
3. Houston-Baytown-Sugar Land, Texas
Robots per 1,000 workers: 3.375
4. Phoenix-Mesa-Scottsdale, Arizona
Robots per 1,000 workers: 2.163
5. Detroit-Warren-Dearborn, Michigan
Robots per 1,000 workers: 1.7
6. Milwaukee-Waukesha-West Allis, Wisconsin
Robots per 1,000 workers: 1.629
7. Philadelphia-Camden-Wilmington, Pennsylvania-New Jersey-Delaware-Maryland
Robots per 1,000 workers: 1.505
8. San Jose-Sunnyvale-Santa Clara, California
Robots per 1,000 workers: 1.438
9. Indianapolis, Indiana
Robots per 1,000 workers: 1.434
10. Cleveland-Elyria, Ohio
Robots per 1,000 workers: 1.289
While the use of robotics to automate work is on the rise, the impact can be either favorable or unfavorable to humans, depending on the type of work they do and how machines may be able to enhance their jobs, the report's authors say.
"Our evidence does not mean an individual will lose their job," William Rodgers, co-author of the report and professor at Rutgers University, tells CNBC Make It. "Our estimates identify the odds or risk of a robot potentially displacing or having a positive impact on employment and wages. Many factors inside the company will ultimately dictate the outcome."
The report found robots had the biggest negative impact among workers in manufacturing, where there are about two robots for every 1,000 human workers. Younger manufacturing workers between 16 to 24 years old who did not attend college saw the biggest decrease of job opportunities and wages, as use of robots increased in the workplace.
However, robot adoption seemed to improve the number of job opportunities for others outside of manufacturing. It's possible that workers displaced by robots were able to find jobs in another industry that paid more.
Additionally, "the adoption of robots could have had a stimulating effect," Rodgers says. Automation efforts may have increased worker productivity, and wages may have increased as a result.
Overall, the increase of robots at work hasn't had a major impact on total employment. According to the report, that's likely because workers displaced by machines have been able to find other lines of work, especially given the recent tight labor market where there are more open jobs than there are people to fill them. The period following the Great Recession also saw historic economic expansion and job growth across the country, so creation of new jobs may have counterbalanced against jobs lost due to automation.
Rodgers notes that this kind of research indicates the need for both workers and employers to continue adapting to new lines of work as the use of robots in the workplace continues to grow.
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