Things were looking pretty bleak back in March for bond exchange-traded funds. The Covid-19 selloff created a liquidity crunch that drove their prices to trade at deep discounts to the value of the underlying assets. Skeptics questioned whether these products could ever be trusted again.

Then the Federal Reserve stepped in. On March 23, it announced that that it would begin buying corporate debt ETFs. This ignited a wave of front-running investments and served as a stamp of approval for the market sector.

A thank-you note to Jerome Powell may be in order. Flows into U.S. fixed-income products this year have surpassed the total for all of last year. New funds are coming down the pipeline. And investors are increasingly using corporate bond ETFs to bet on an economic recovery and hedge against what could be a volatile post-election season.

“The events from the onset of the pandemic have only accelerated the growth of fixed-income ETFs,” said Matthew Bartolini, head of SPDR Americas Research at State Street Global Advisors.

So far this year, inflows to bond funds total $170 billion, compared with $154 billion in all of 2019, according to data compiled by Bloomberg.