Most millennials maintain appropriate allocations to equities given their age and financial goals, according to a research paper published Tuesday by Vanguard.

Researchers found that the typical millennial investor allocates 90% of his or her portfolio to equities, which it said was consistent with certain professional portfolio allocations.

Vanguard’s Center for Investor Research assessed household risk-taking by analyzing 4 million Vanguard retail investor households holding a combination of IRA and taxable brokerage or mutual fund accounts.

(Related: Should Young Retirement Investors Really Go All-In on Risk?)

The research also found that like other generations, millennials have been adopting balanced investing strategies.

During the 2012–2017 period, investors of all ages shifted away from extreme equity allocations — from 38% with all equities or zero equities to 33%, Among millennials, the share of investors with extreme allocations dropped from 45% to 38%.

This change could be attributed in part to increased use of target date funds, according to Vanguard. Among IRA holders in the sample, about one-third of all millennials owned TDFs.

Vanguard says its 2018 defined contribution benchmarking report complements these findings on the increasing use of TDFs: 82% of plan participants younger than 25 allocated their portfolio to TDFs, while 67% of those between 25 and 34 were invested in these funds.

“Target date funds are reshaping investor behavior of millennial and Gen X investors, with the potential to improve outcomes over an investing lifetime,” the paper’s author Jean Young said in a statement.

“Younger investors are benefiting from balanced, diversified portfolios, and shifting away from the extreme equity allocations that we’ve witnessed in the early years of previous generations.”

The paper said that although most millennials hold age-appropriate allocations, a growing number hold zero-equity portfolios — 19% in 2017, seven percentage points higher than in 2012.

One reason, according to the research, may be bear-market experience that has caused some investors to adopt conservative portfolios. In 2007 and earlier, only 10% of millennials held zero-equity portfolios, while 33% held all-equity portfolios.

During and after the crisis, 22% of millennial investors held no equities in their portfolios, and just 14% held all equities.

Vanguard researchers suggested that inertia could also account for zero-equity portfolios, as new investors hesitated to put money in the stock market. A third of millennials who opened their first account in the past year held no equities, for example, though this figure drops sharply as tenure increases.

Yet another reason, they said, could be short-term goals, such as a house purchase.

Other recent research found that while millennials have age-appropriate attitudes toward asset allocation — 66% agreeing that the more time they had until retirement, the more aggressive they could be with their investing strategy — 66% of millennials surveyed felt safest keeping most of their savings out of the market or putting it in real estate.

— Check out Millennial Homebuyers Could Be Making a Big Financial Mistake on ThinkAdvisor.