Both contribute; however, the difference between 70% and 90% is large. NPR fails to mention that this makes good financial sense. Increasing the vaccination rate in your workforce decreases the number sick employees, which reduces paying overtime, etc. It's strange to me that my previous Health System employer mandated that we get flu shots (not doing so was cause for termination), however it has no mandate regarding the COVID19 vaccine.
if you do benefit analysis, rather than cost benefit analysis. It's hard to predict how effectively promoting vaccinations will reduce sickness. The vaccines are not perfectly effective, and people are likely to risk-compensate. Vaccinated employees who become more casual about health protocols could be bad for business. There is risk of a backlash among employees who are not enthusiastic about getting the vaccine.this makes good financial sense