Far from their reputation as speculative daredevils, millennials are embracing bond exchange-traded funds to a greater degree than other generations as muscle memory from past recessions kicks in.

That’s the finding of an annual study by Schwab Asset Management, which shows that ETF investors born from roughly 1981 to 1996 have 45% of their portfolios in fixed income. That compares to 37% for Generation X — those born from around 1965 to 1980 — and 31% for baby boomers, although older generations may hold debt through mutual funds or other structures. Interest in fixed-income is rising as well, with 51% of millennials planning to invest in bond ETFs next year, versus 45% of their Gen-X counterparts and 40% of baby boomers.