(Bloomberg) -- More than 40% of all US mortgages were originated in 2020 or 2021, when the pandemic drove borrowing costs to historic lows and triggered a refinancing boom, according to data from Black Knight.Most Read from BloombergSingapore PM Lee’s Estranged Brother Weighs Presidential RunAmericans Need to Be Richer Than Ever to Buy Their First HomeAmazon Pauses Construction on Second Headquarters in Virginia as It Cuts JobsiPhone Maker Plans $700 Million India Plant in Shift From ChinaAmazon