-The spreadsheet compares the current number of deaths with the current number of known cases. However, deaths will always leak behind the number of confirmed cases; this way you will be underestimating death rate.
-It might also be interesting to do some back of the envelope math on the cases outside of China, since discovery rate should be much higher. So far, there are very few serious, and I think no critical conditions. However, most confirmed infections outside of China are actually people who were infected in China and then traveled overseas which selects for people healthy enough to travel, so mostly younger. Doing a proper analysis of those numbers will be hard; one could compare them to SARS figures of the relevant age bracket.
Just some quick thoughts:
-Your lowest discovery rate (15%) might still be too high, this recent preprint estimates 0.05% https://www.medrxiv.org/content/10.1101/2020.01.23.20018549v2.full.pdf
-The spreadsheet compares the current number of deaths with the current number of known cases. However, deaths will always leak behind the number of confirmed cases; this way you will be underestimating death rate.
-It might also be interesting to do some back of the envelope math on the cases outside of China, since discovery rate should be much higher. So far, there are very few serious, and I think no critical conditions. However, most confirmed infections outside of China are actually people who were infected in China and then traveled overseas which selects for people healthy enough to travel, so mostly younger. Doing a proper analysis of those numbers will be hard; one could compare them to SARS figures of the relevant age bracket.