Yes, they need to be recent. Amazon is constantly asking, "What have you done for me lately?"Kayla Dawn Thomas said:That makes sense. I had good sales last summer, but they've dwindled over the winter. Do they need to be pretty recent? In some cases I have as many or more reviews than the books on the first page of my categories.
The idea is that, next batch of promotions you run, your books might be a bit stickier because of the optimized keywords.