Reports of incivility against frontline employees are on the rise, according to a new survey conducted by Georgetown University management professor Christine Porath, who’s studied incivility for more than 20 years. She defines incivility as rudeness, disrespect, or insensitive behavior, and has published her results in the Harvard Business Review.  

“People are nastier than ever to frontline employees. The effects are costly to those who serve us, witnesses, businesses, and society. I hope we improve,” Porath told Fortune.

Out of 2,000 frontline employees and people who observed them at work, surveyed across 25 industries around the world, around 76% said they experienced incivility at least once a month. And another 78% said they witnessed incivility at work specifically at least once a month. But those numbers don’t quite capture the scale of the problem: Around 70% said they witnessed incidents of rude behavior at least two to three times a month. 

Those numbers are much higher than they were just a few years ago. In 2005, when Porath conducted a similar study, “nearly half” of workers said they were treated rudely at work once a month. When she asked again in 2016, that number was up to 62%. 

In other words, it seems that the world is on a bad trajectory, and people are taking note. Around 78% of people in the latest survey said customers being rude to employees is more common than it was five years ago. And 73% of respondents said bad behavior is “not unusual,” compared to a 2012 customer-incivility survey when that number was only 61%. 

In follow-up interviews conducted by Porath, one retail worker shared that after saying good morning to a customer, they responded: “I do not need you for anything. Leave me alone. If I need you, I will call you. You are here to serve, not to talk with me.”

Meanwhile, a school principal shared the experience educators often face when dealing with their students’ parents. 

“Parents approach school staff with claws out, ready for blood. They’re unwilling to listen and are rude, mean, and threatening,” they said. 

Porath believes there are several factors that could explain why rude and insensitive behavior is increasing, including the COVID pandemic and a troubled economy, which can lead to higher stress levels. 

“Any (or all) of these factors may contribute to our stress and burnout, which have risen to unprecedented levels recently. And considering our reduced levels of self-care, exercise, and sleep, it’s no surprise that we have a tougher time regulating our emotions,” she wrote. 

Porath also thinks the increase in rude behavior could also be linked to weakened ties in workplace and community relationships, a greater disconnect because of technology, and a lack of self-awareness.

Although she focused on frontline workers specifically, Porath found that rudeness isn’t just confined to the person experiencing it—it can also have an impact on businesses as a whole. 

“Research shows that rudeness is like the common cold: It’s contagious, it spreads quickly, anyone can be a carrier—at work, at home, online, or in our communities—and getting infected doesn’t take much,” Porath said. 

When people see customers being rude to employees, 85% report being annoyed and 80% report being upset. Their attitude toward the organization where the bad behavior took place also changes. Around 40% question whether they want to do business there again, and 65% think the organization should better protect its employees. Perhaps most ominously, their willingness to use a company’s products and services—after witnessing a customer’s hostility toward an employee—drops 35%.

But there are ways business leaders can address incivility, Porath said. That can mean training employees on how to handle bad behavior directed towards them, encouraging employees to show empathy, and recognizing and showing appreciation for the work their employees do.