Gen Z will make up a larger portion of the U.S. workforce than Baby Boomers for the first time next year, according to a recent Glassdoor trend forecast report — and it's a big deal, says an economist.

The looming change in demographics will have "pretty sweeping implications for what employers prioritize," Glassdoor chief economist Aaron Terrazas tells CNBC Make It. "This is the tail end of the Boomers, this transformative generation for work in the workplace. They are being replaced by very different people who prioritize different expectations around work."

The trend is driven by aging: By most definitions, Boomers will range in age from 60 to 78 next year, and are reaching retirement. Gen Zers, aged 12 to 27 next year, are increasingly graduating school and joining the workforce.

Eventually, Gen Z will overtake Gen X too — but it'll be "a long time before they overtake millennials," says Terrazas, because millennials outnumber all other generations in the United States so far. "It probably won't be until the early 2040s."

Here's why the shift matters, and what could happen to workplaces across the country, according to Terrazas.

Gen Z brings different values and expectations to the workplace

Gen Z is coming of age in a strikingly different time than Boomers — an atmosphere marked by political turmoil and the Covid-19 pandemic. "So, their overall attitudes about work and what they expect are different from their grandparents," says Terrazas.

These younger workers have a stated preference for employers with demonstrated social impact, upward mobility and creative opportunities, according to a national survey conducted in 2022. Gen Z "value flat organizations and they want their opinion and perspective heard, irrespective of their experience or tenure," Terrazas adds.

Similarly, they're more likely than other generations to want to get political at work, and they expect company leadership to be vocal about the issues that they care about, says another Glassdoor report published last month.

Gen Zers are particularly concerned with the tradeoff between work and leisure, Terrazas says: They tend to value flexible jobs that can help enable a healthy work-life balance, which they can view as more precious than job security. Perhaps ironically, they also overwhelmingly prefer in-person work interactions, notes a recent Fiverr survey.

″It doesn't necessarily have to be in the office," Michal Miller Levi, Fiverr's senior director of market research and customer insights, told Make It last month. "Almost a third prefer working in public places like coffee shops where they can meet and interact with people while keeping their flexibility."

As early-career workers, many Gen Zers value development opportunities and regular feedback: 73% of them are willing to quit their jobs if their managers don't provide both, found a survey published earlier this year by HR software company StaffCircle.

And they're not afraid of job-hopping if they find their work situations unsatisfactory, noted a January LinkedIn report.

"That's going to prompt a lot of soul searching at the executive level about the ways to retain and motivate their employee base, particularly these youngest employees," says Terrazas.

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