Sometimes it is necessary to state the obvious. The efficacy of the vaccines, not complete to start with, falls away rapidly. This is demonstrated by a graph from November, from a study based on a cohort of military veterans in the US:
The Covid Vaccines Have Failed
Published by markskidmore
Mark Skidmore is Professor of Economics at Michigan State University where he holds the Morris Chair in State and Local Government Finance and Policy. His research focuses on topics in public finance, regional economics, and the economics of natural disasters. Mark created the Lighthouse Economics website and blog to share economic research and information relevant for navigating tumultuous times. View more posts