The amount of assets held in exchange-traded bond funds has pushed past $1tn, capping a near fivefold increase since the financial crisis, and underscoring a radical reshaping of the world’s debt markets.

ETFs — passive vehicles that try to mimic the performance of an underlying index — have emerged as fixtures of many investors’ portfolios over the past 30 years, giving them relatively cheap and reliable access to a wide variety of assets, from gold to stocks to bank loans.

Equity ETFs continue to dominate the $5.6tn-in-assets industry, but the rapid rise of fixed income ETFs highlights how investors have become increasingly comfortable using such vehicles as tools for trading, and to build up broad bond portfolios. Assets in bond ETFs came to $1.03tn at the end of March, according to ETFGI, a research provider. At the end of 2009 the equivalent figure stood at $218bn.