The coronavirus continued to weigh on the U.S. labor market last week.

New applications for unemployment hit 6.6 million in the week ended April 4, Labor Department data showed Thursday. The prior week, originally reported at 6.6 million, was revised to 6.9 million.

Claims from three weeks ago were also revised upward. These rose from around 1 million for the week ended March 21 to 3.3 million.

A staggering 16.8 million Americans have been thrown onto the unemployment rolls in just three weeks, underscoring the terrifying speed with which the coronavirus outbreak has brought world economies to a near standstill.

The CARES Act expanded the ranks of those eligible to file claims for unemployment benefits and raised the amount paid to unemployed workers. Self-employed workers and independent contractors can now file for benefits, expanding the number of claims.

New claims for state unemployment benefits are a proxy for layoffs. Released weekly, they are some of the few real-time indicators of economic conditions.

Actual job losses may be higher than the most recent figures reveal. Applications in many states have been hampered by websites and phone lines failing due to the rapid rise in the volume of claims.

–The Associated Press contributed to this report.