As of this morning, S. Korea (the country with the best surveillance data) has 8,162 confirmed cases and 75 deaths (an average case fatality rate of 0.9%).
But the case fatality rate varies a lot with age. Of the deaths in S. Korea, 25 have been over 80 years old, and 28 between 70-79 y/o. Fourteen were between 60-69 and 6 deaths have been among people 50-59 y/o.
Seventy-one percent (71%) of the deaths in S Korea are among people 70 years old and above and 89% are among those over 60. The case fatality rate for those over 80 is about 9%, and for all those over 70 it’s about 6.7%.
However, for people under 40 years it’s just 0.04% or 4 in 10,000. You can see from those data that COVID-19 is far more serious among those over 70 years old, and that for those under 40 it’s really not all that lethal.
The South Korean CDC updates their surveillance daily in English, and you can explore their data by going to this website.
