- The plague killed 50-100% of people who got it depending on which kind of plague you got (bubonic, pneumonic or septicemic) whereas while nCoV rates are still TBD we're probably looking at an upper bound closer to half a percent, or 3-4 order of magnitude lower.
- The average age of folks who've died of nCoV so far in Italy is 80 and in China the mid-high 70s.
- The plague took everyone whereas the young and healthy are effectively going to get a (sometimes very, very) bad cold out of nCoV. The younger they are, the less affected. I think out of the hundreds of thousands of cases we know about so far only a single child has died -- and they had serious medical conditions going in. Currently the CFR in Korea and in the USA for people under 30 is less than 0.1%.
Perspective matters. It's easy to get swept up in the panic going on right now. Don't panic. Do listen to authorities and generally keep away from other folks. This will all be over in a few months. We'll mostly all get it, we'll overwhelmingly recover, and become immune. Chances are this is going to become one of the endemic viruses that shows up every year from now on.
As panic sets in, if you've got some cash to invest in the markets and a long time horizon to draw on it, this may be the money making opportunity of a generation.