We’ve waited far too long for a scientific study of waiting. From queues to telephone holds to waiting rooms, delays are all around us and they’re miserable. And according to new research just published in Nature Human Behavior, lower income people and Black people of all income levels get stuck with more of it than others.

Waiting is a form of time theft. By making us wait, government institutions and private companies steal precious moments we could have spent working, vacationing, resting, tending to our relationships or getting other things done.

Richer people can often pay to avoid waiting — such as taking a special security line at the airport or driving to work rather than waiting for public transit. These options are less open to poorer people. And waiting is often worse in poorer parts of town, where supermarkets tend to have fewer cashiers and bus service may be spottier.

But sooner or later, we all have to wait. And it’s frustrating. “That experience of having your time wasted is uniquely offensive, insulting, upsetting,” says Syracuse University political science professor Elizabeth Cohen, author of “The Political Value of Time.” “Time is a unique resource and once that segment of your life is gone, you’re never getting it back.”

Stephen Holt, an associate professor of public affairs and policy at the University at Albany SUNY, and an author of the Nature paper, said he’d previously studied voluntary time use, starting with a study of gender differences in study times.

He realized that self-reporting can be biased — people tend to report more time than they actually spend exercising or studying or whatever the researchers are trying to measure. But he found the Bureau of Labor Statistics gathered a more neutral source of data — time diaries where a diverse cross section of people were asked to catalogue what they were doing each hour of a single day. (And yes, he found girls study more than boys.)

Then, a year ago, he started thinking about involuntary time-sinks after his wife reported having to wait two hours in an optometrist’s office. She was surprised how many other people seemed to accept this outrage. He checked to see if waiting time was included in those Bureau of Labor Statistics diaries, and found at least some forms of waiting were, such as waiting for services like checking out at a grocery store.

It’s no surprise that poorer people waited more — but the study was important for confronting the question with scientific research, and for calling attention to a problem so commonplace it fades into the background.

The overall time gap was smaller than I would have guessed — people making under $20,000 a year waited, on average, six hours a year more than people making over $150,000 — but Holt said the survey data he used could only capture a fraction of the total. The time diaries were just from 24-hour periods, so they caught gaps in daily activities. The worst wait times happen less often — at the doctor’s office, for example, or Department of Motor Vehicles.

And even though poorer people waited about 15 minutes longer each shopping trip, the difference was blunted by the fact that they probably compensated by shopping less often, and therefore buying more processed foods and less fresh items.

One mystery was that the income gap appeared in all racial groups except Black people, whose waiting time across the board was as long as poorer people in other groups. Why would that happen? Some of it might be a consequence of anti-Black racism, with Black people just getting slower service, Holt said. Then there are the effects of ZIP code. If you live in a less-white neighborhood, you may be stuck in a crowded supermarket while suburbanites are breezing through the checkout at a better-staffed Whole Foods.

Or some of it could be an artifact of limited data. This study was not meant to be the last word on waiting but an introduction to an understudied and underappreciated problem and source of inequality on our society. The one-day time diary data could easily miss many of the more occasional but painful waiting situations — including hours spent in hospital ER waiting rooms or standing in lines at government agencies.

In those cases, ZIP code can make all the difference. In Washington, D.C., where Holt used to live, there were stark differences between one DMV and another. Same in Rhode Island, where I once walked into the facility closest to my home only to have to wait in a line to figure out which line to wait in. I turned around and drove to another smaller, nicer, less crowded office 40 minutes away.

That drive wasn’t crazy, said Cohen. “We know from anthropological and psychological work that … waiting where you don’t know when it’s going to end is a form of torture.” Indeterminant waiting also makes it impossible to plan your day — whereas I bought myself the ability to re-plan my day by taking a time-consuming sure thing over a mystery. That was only possible because I wasn’t trying to regain a revoked license, had valid plates and could afford the gas.

And the survey didn’t include those time-stealing forms and applications that Cohen calls administrative burden — something that’s particularly bad when trying to apply for unemployment benefits or SNAP (food stamps). “Those are intentionally burdensome to make it difficult for people to access social benefits,” she said. When the government wants you to take a service, they can make it easy. It was shockingly quick, for example, to get four government-supplied COVID-19 tests.

Private companies also burden people with time-consuming forms when they make a mistake on a bill or when an airline cancels a flight. If you want your money back, it usually costs you quite a bit of time.

As Benjamin Franklin once warned, “Time is money,” and yet we let people steal our time with impunity. And unlike money, we can’t ever get it back.

(Faye Flam is a Bloomberg Opinion columnist covering science. She is host of the “Follow the Science” podcast.)