The pace of Covid-19 deaths will drop sharply in the next four weeks, according to a new forecast that shows a brutal wave of cases ebbing and the U.S. plodding forward with vaccine distribution. The nation is expected to have about 12,666 deaths in the week ending March 13, according to the University of Massachusetts’ Reich Lab’s Covid-19 Forecast Hub, which issued a four-week forecast Tuesday. The prediction is based on independent models collected in collaboration with the U.S. Centers for Disease Control and Prevention.

The toll would be a drop of 43% from the 22,062 deaths reported last week, according to Johns Hopkins University data.

though cases have been declining for a month, deaths — a lagging indicator — haven’t dropped much from record levels, the Johns Hopkins data show. That should start to change this week, and the numbers are likely to improve gradually over the four-week period. The pace would be the slowest since the period ending Nov. 28.