Investor interest for ETFs continues to gain momentum, with an increasing number of mom and pop investors looking into the nifty investment vehicle.

According to Charles Schwab data on its trading platform for the first quarter of 2018, ETF assets custodied at Schwab hit $423 billion, or up 27% year-over-year, reflecting rising interest for the ETF investment vehicle.

Breaking down the the ETF assets custodied at Schwab into the separate investor groups, ETF assets among retail traders rose 37% to $55 billion, ETF assets under retail investors rose 26% to $147 billion and ETF assets managed for RIA clients rose 25% to $221 billion. The pop in retail trader assets may have reflected the increased trading in a volatile first three months of the year.

Related: ETF Market Is Swimming in Liquidity at the End of the Day