Contrary to belief, worker pay isn't broken

"Workers are delivering more, and they're getting a lot less," argued former Vice President Joe Biden in a speech at the Brookings Institution this summer. "There's no correlation now between productivity and wages."

U.S. Sen. Elizabeth Warren, a Democratic presidential rival, agrees. Her campaign website states that "wages have largely stagnated," even though "worker productivity has risen steadily."

The claim that productivity no longer drives wages is common enough on both the political left as well as the right. Proponents of this view argue that workers aren't getting what they deserve based on their contributions to employers' bottom lines.

Income inequality — the gap between the incomes of the rich and everyone else — supposedly demonstrates that the economy's rewards are flowing, undeservedly, to those at the top. Populists take that conclusion even further, arguing that capitalism is fundamentally broken.

If that is what's happening, it refutes textbook economics, which argues that wages are determined by productivity — by the amount of revenue workers generate for their employers. If a company paid a worker less than her productivity suggests she should be making, then she would go down the street and get a job that would pay her what she's worth. Employers compete for workers, ensuring that workers' wages are in line with their productivity.

This theory leaves out a lot, of course. Pay and productivity can diverge for any number of reasons not included in the standard economic model. Workers may not know how much revenue they create, or what other employment options are available to them. And changing jobs has its own costs, which in the real world gives employers some power over wages.

For critics of the current system, "some power" is a drastic understatement. In their telling, the decline of labor unions; erosion of the minimum wage; rise of noncompete and no-poaching agreements; inadequate enforcement of workplace standards and the like have dramatically reduced the bargaining power of workers. This has allowed businesses to drive down wages to the bare minimum job applicants and current workers will accept, pushing their pay below what their productivity suggests it should be.

Like several previous studies, Lazear's research finds that low-, middle- and high-wage workers all benefit from growth in average productivity. This suggests that improvements in overall economic efficiency help all workers, not just the rich.

But Lazear argues, correctly, that a relevant issue is not whether workers benefit from changes in average productivity. Instead, if you want to know whether workers are being paid for their productivity, you should look at whether changes in the productivity of, say, low-wage workers affect the pay of that specific group.

It is infeasible to measure the productivity of individual workers. (How much revenue per hour of work do I generate for Bloomberg?) So Lazear examines productivity at the industry level, and compares industries that employ highly skilled workers with those that employ lesser-skilled ones.

Using data on the U.S. from 1989 through 2017, Lazear finds that productivity in industries dominated by higher-skilled workers increased by (roughly) 34% in that period. The wages of those workers grew by 26%. For industries requiring lesser skills, productivity increased by 20%, while wages grew by 24%.

In other words, pay increased faster than productivity in industries with lesser-skilled workers, and slower than productivity in industries with higher-skilled workers. Another striking implication of this finding is that "productivity inequality" — the gap in productivity between workers — may have grown faster than wage inequality over this period. While wage differences have increased over time, differences in productivity between groups of workers have increased even more.

What caused this? Lazear points to two familiar explanations. Technological change disproportionately benefits the highly skilled, increasing their wages and productivity. And the globalization-led shift to a services economy has reduced the productivity of goods-producing, lesser-skilled workers.

Lazear also suggests that colleges may have improved more than high schools in their ability to impart skills to graduates. If so, industries dominated by college graduates would be expected to have had faster productivity growth over the last three decades. This would have caused both a wider dispersion in productivity across industries and in wages across groups of workers.

Such research doesn't settle the debate, of course. Yet it does strengthen my view that wages are heavily influenced by market forces, even if they are not entirely determined by them. While productivity sets the baseline for wages, deviations from that baseline occur.

So contrary to what Biden, Warren and (many) others say, market forces, not power dynamics, are the principal driver of inequality.

This gets at the heart of the moral properties of the market economy. Capitalism produces unequal outcomes: The wages for some grow faster than for others. Those disparities are palatable if they are caused by differences in risk-taking, work effort and skills. They are tolerable if people are getting, in some sense, what they deserve. But if wages aren't determined by productivity — if hard work doesn't pay off and if workers aren't receiving just returns — then something has gone badly wrong with the system.

Michael R. Strain is a Bloomberg Opinion columnist. He is director of economic policy studies and resident scholar at the American Enterprise Institute. He is the editor of "The U.S. Labor Market: Questions and Challenges for Public Policy."