From https://www.statista.com/statistics/241572/death-rate-by-age-and-sex-in-the-us/ https://www.statista.com/statistics/241572/death-rate-by-age... Looks like

From https://www.statista.com/statistics/241572/death-rate-by-age-and-sex-in-the-us/ https://www.statista.com/statistics/241572/death-rate-by-age... Looks like 6% of 80-84 and 14% of 85+. Someone better at statistics than me could probably say what the relative and absolute risk increase is for contracting COVID-19 at those ages is. Search for "all cause mortality by age" if you want to do some more research.