Last year, the pair of economists
were much more buoyant about the fate of human workers in the face of automation. But now they estimate that robots
are to blame for up to 670,000 lost manufacturing jobs between 1990 and 2007, it concluded, and that number will rise because industrial robots are expected to quadruple.
Acemoglu and Restrepo reckon the increase of 1 robot per thousand workers reduces employment rates (by between 0.18 and 0.34%) and wages (by between 0.25 and 0.5%). Another way to look at this is that every additional robot reduces employment by 5.6 workers.
Measured by intensity, that is how many robots are used per human worker, the US is far off the leaders. The most robo-intense manufacturers are in Asia. South Korea, which tops the list, has more than 500 robots per 10k manufacturing workers. In the US, that ratio is a more pedestrian 180-200. (That is still above the UK at fewer than 100 robots per 10k human employees.)
If, and it’s a big if, US factories get as automated as those in South Korea, we would see an additional 500-600k robots come on stream. And extrapolating from the NBER data, that would increase pressure on 2.5 and 3m manufacturing jobs (and the attendant wages of the remaining workers in the sector).