I suspect that it might be curved rather than a critical peak; possibly might bottom out sooner too...
Other than that, as near perfect as I've ever seen...
An archaeologist friend summed it all up shortly before he took early retirement, once he'd lost his
work buddy (2ic) to a neighbouring county in his rank... he used to call his compatriot "his little monkey"...
I used to comment about my job a decade back that I just
don't give a monkey's anymore, and he'd reply that he
didn't have one to give...