Exercise 18.1: is this about total regret or average regret?

So this exercise asks us to prove that swap regret of an action sequence of length T can exceed its external regret by at least T.

It's easy to show that the total swap regret can exceed the total external regret by at least T if the player also swaps to the winning side. However, since both regrets are defined as average regret, it seems impossible to get a total difference of  T^2 and then get averaged difference of T. Is this a typo or am i missing something?

Thanks!