Plan participants using a self-directed brokerage option in their 401(k)s had a brutal fourth quarter.

Retirement plan participants using self-directed brokerage accounts with Schwab lost on average more than 10 percent of their account balances during the fourth quarter of 2018, according to Charles Schwab’s SDBA Indicators Report. For the year, the average loss was about 6.3 percent.

Yet despite the volatility, participants averaged 2.2 trades a month during the period.

At the end of the fourth quarter, the average self-directed brokerage account balance was $246,153, according to Schwab’s analysis of over 130,000 accounts.

Mutual funds accounted for 37 percent of the assets in self-directed brokerage accounts, making them the most popular investment option. Equities came in second, accounting for 28 percent of the assets, followed by ETFs, 17 percent; cash, 15 percent; and fixed income, 3 percent. On average, participants held 10 positions in their accounts.

Looking more closely at mutual fund allocations, 28 percent of mutual fund allocations were in large-cap equities, followed by taxable bonds with 21 percent, international funds with 16 percent, and hybrid and small cap funds each with 12 percent. U.S. equities were the most popular allocations for ETFs, accounting for 48 percent of the assets, followed by international equity with 16 percent and U.S. fixed income with 15 percent.

In allocations to stocks, Apple was the top overall holding, accounting for 9 percent of all equity allocations within portfolios, followed by Amazon with 6.5 percent and Berkshire Hathaway with 3 percent. Microsoft, with 2 percent of the assets, and Facebook, with 1.75 percent of the assets, rounded out the top five stock holdings.

Men are significantly more likely to use self-directed brokerage accounts as part of their 401(k): 76 percent of the accounts were held by males, while 24 percent were held by females, according to Schwab. The average age of a participant was 51.

Schwab analyzed data from about 137,000 self-directed brokerage accounts with balances between $5,000 and $10 million.