Reading is fun. The books that we read start dialogues and introduce concepts that we won't remember until we think of them in association with something else.

Reading is fun. The books that we read start dialogues and introduce concepts that we won't remember until we think of them in association with something else. That the OP has to try and justify reading to himself in some sort of rigorous quantitative fashion is just sad. And I remember plenty of what I read just fine. (Enough of it to satisfy my requirements to keep doing so.)