Now, there's an exchange-traded fund looking to capitalize on millennials' emerging buying power.
"Companies well-positioned to target millennials are those likely to do well," said Bruno del Ama, founder and CEO of Global X Funds, which launched the Global X Millennials Thematic ETF last week.
"It's generally bad to bet against the American consumer. And millennials are increasingly becoming part of the American consumer. In fact, they're the growth engine," he told CNBC's "Squawk Box," saying millennials earn roughly $2 trillion, with projections of income growth to $8 trillion by 2025.
Millennials passed baby boomers in 2015 as the nation's largest living generation, according to population estimates released by the U.S. Census Bureau in April. Boomers, currently ages 51 to 69, number 74.9 million. But millennials are now 75.4 million strong.
"We're ready to bet on millennials," he said.
The top holdings of Global X Millennials Thematic ETF include stocks many investors would expect, such as Facebook, LinkedIn and Amazon, which take advantage of the tech tendencies of millennials.
But some names might be more surprising like real estate investment trusts AvalonBay Communities and Equity Residential, and Home Depot, which could benefit from millennials moving out of the home of their parents.
The Global X Millennials is the ninth ETF in Global X's suite of thematic funds. "Thematic investing ... is a type of investing that institutions have been very focused on," looking at emerging growth patterns, del Ama said.