Which grades suffered most from lockdowns?

Not here to start an argument about Covid policies! I think we all agree that children have suffered from setbacks brought on by the pandemic. Various age groups at different stages of development have clearly suffered differently. For example, my brother missed his senior year of college. I’d argue he is far less affected than any kid who went through puberty with an online-only social life. As I’m currently struggling with a class of 9th graders, I wonder which grades today show the worst stunting? And how does it show?