There's been an increasing amount of evidence that having Millennial employees (those between the ages of 18 and 34) is essential for a healthy startup. 

From a marketing standpoint, it makes sense: This generation accounts for a staggering $200 billion of spending power in the U.S. alone.

Increasingly, Millennials are managing their Gen X and Baby Boomer counterparts in the workplace, according to a new study from consulting firm Future Workplace. The data was pulled from a survey group of 6,000 people of varying age groups.

83 percent of respondents said they'd seen Millennial managers in their offices. Given that Millennials are the largest generation in the U.S. workforce (80 million in population), it shouldn't come as a surprise that they're rapidly taking over managerial positions. Still, that doesn't mean everyone is happy about it. 

"As more Baby Boomers retire, Millennials are moving into leadership positions and are faced with managing older generations, which they were never trained to do," noted Dan Schawbel, the research director at Future Workplace, in the report.

The data revealed that nearly half (45 percent) of older generations believed those Millennials to be ill-equipped to manage a team, and feared that they might have a negative impact on the company.

"The only way to overcome this unique challenge is through a range of professional learning and development delivery options, including formal training, mentoring, coaching, and online self-directed learning," added Rich Milgram, the founder and CEO of Beyond, the a networking platform that partnered up to complete the study.

Before you jump to the conclusion that Millennials aren't qualified to hold leadership roles, however, consider the many attributes they do bring to the table

They've reinvented productivity by eliminating archaic performance reviews -- and instead, have created new metrics. Chip Espinoza, author of Millennials Who Manage, noted in a recent Fast Company interview that the generation has been recognized as being more "relational" -- meaning they have a higher level of emotional intelligence.

What's more, while Baby Boomers may think that Millennials are less productive (perhaps due to the common "smartphone addiction"), there's no argument about their ability to consume vast amounts of information across multiple technology platforms.

The Millennial urge for inter-connectivity in a digital world could be an indication of compassion -- perhaps even more so than previous generations. "We want so desperately to connect with the world, and sometimes technology is the only outlet we have," said Stacey Ferreira, in conversation at last month's Inc. Women's Summit in New York City.

The study suggests that regular mentorship and leadership coaching programs will ultimately benefit both Millennials and their Gen X or Baby Boomer staffers. While 44 percent of Millennial respondents viewed themselves as capable managers, just 14 percent of all respondents agreed.

Meanwhile, about one third of those Millennials admit that it's difficult to manage older peers.

As always, it's important to keep in mind the incredible diversity of this, or any, generation. David Berstein, the entrepreneur and author of Fast Future: How the Millennial Generation Is Shaping Our World, says it best: "You cannot make generalizations about an entire group of people."