Every number tells a story. So far, the story of coronavirus has largely been told in death counts. Assembled by epidemiologists and public health leaders, those figures paint a picture of devastating loss: Out of more than 9 million cases worldwide, nearly half a million people have died.
But there’s another number that tells a slightly different story. Some public health wonks use another measure of mortality you may not be familiar with: years of life lost, or YLLs. Based on early averages, Covid-19 cuts 12 to 14 years off the lifespan of its victims.
Both YLLs and total fatalities reflect the astounding mortal cost of coronavirus. But they highlight different aspects of the challenge facing every country in the world. And it’s important to understand what each of them can and can’t tell us about the progression of the virus through society.