The U.S. and Europe saw record declines in business activity in March, as economic activity slowed around the world due to measures aimed at containing the new coronavirus.

Data firm IHS Markit said its composite purchasing managers index for the U.S.—an aggregate measure of activity in the manufacturing and services sectors—dropped to a seasonally adjusted 40.5 in March from 49.6 in February. That was a record low for the 10½-year-old series, which started after the 2007-2009 recession. The comparable index for the eurozone...