Excess deaths among Black people jumped in 2020, reversing years of progress in reducing the gap in mortality compared with White people, a new study found.

Over two decades, the Black population in the U.S. suffered 1.63 million excess deaths and more than 80 million excess years of life lost due to increased mortality risk relative to that of the White population, the report published Tuesday in the journal JAMA Network Open said. The study was based on death certificate data between 1999 and 2020 from the US Centers for Disease Control and Prevention.

The study found the age-adjusted death rate among the Black population declined until 2011, shrinking the disparity in excess deaths compared to the White population. Progress stalled until 2019, and the gap widened again in 2020.

Researchers said in the study that Covid-19 contributed to the higher rate of excess deaths among Black people reaching "rates of excess mortality and years of life lost not seen since 1999."

"Over the last twenty years, the first part of those two decades we were making progress," Dr. Harlan Krumholz, the lead study author and a cardiologist and professor at Yale School of Medicine, told CNN. "Soon after the economic disruption with the financial crash, the whole improvement stalled, and then with the pandemic we did so much worse."

The researchers used statistical analyses to estimate age-adjusted excess mortality rates and potential years of life lost for each population group. The study also looked at trends in these measures according to causes of death and age.

Middle-aged Black Americans and infants had the highest rates of potential years of life lost, according to the data. Disparities in deaths from heart disease were the largest driver of differences in excess deaths between Black and White people. Gaps in deaths from cancer among men were also an important driver.

The study shows continued disparities in mortality rates and potential years of life lost among Black and White populations in the United States.

"There is no biological reason why Black people should have a higher mortality rate than White people. It is a function of our social construct of our society, the legacy, and the history and the persistence till today of structural racism in society," Krumholz said.

He emphasized that more work needs to be done around health disparities and race.

There may be known limitations in retrieving data from death certificates as there may be reporting inaccuracies on race and ethnicity, the report said.

"We ought to take these kinds of metrics -- excess deaths and years of life lost -- and make them National Health Equity metrics and be accountable to them and begin to come up with new ideas," Krumholz said, adding, "We need new ideas to create sustainable change, we need new investment, and we need to be able to try harder to make a difference."