My figure is correct, the 11.7yr is wrong. It's a pretty good paper, but 2 major flaws that I think should be corrected.
From the paper:
> Both of the above calculations may overstate the loss of remaining life in that they assign the remaining life expectancy based only on age, without taking into account that COVID-19 deaths are disproportionately occurring among those with compromised health status.
So their 11.7 average years remaining ignores the critical bit of information that we know this person died of COVID. It is extremely unlikely that if you took 2 80 year olds, one who died of COVID and one who did not, that if neither got COVID they would live to be the same age. I wouldn't be surprised if it was a 10x difference. While they do mention this and add some caveats (a good thing), I think because it completely changes the conclusions of the paper, they should have gone with a range and not a 11.7 number, which seems very improbable.
> Avoiding 1.75 million deaths or 20.5 trillion person years of life lost would be valued at $10.2 to $17.5 trillion
Then they take the 11.7 figure from above and multiply it by the estimated average value of a year of life. Again, there is at least an order of magnitude difference between a year of life at age 90 and a year of life at age 30, for most people.
Finally, although my ~3.5 number is much closer to the truth than 11.7, there is a difference between life expectancy and "healthy lifespan", aka "healthspan" (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6136295/). Healthspan is a newer concept but I expect will be the primary term in a decade or two.
Thank you for providing the link, a good read.