Students may like the reading assignments (I did), being having them listed isn't the same draw as being given a story prompt that fuels a brainstorm of ideas.
I didn't mean to offend you with my comments. H Dean's initial post made it seem like there was a general shortage in Level Two and beyond, but it doesn't seem like the statistics really bear that out; it is a pretty regular pyramid, it seems, which would obviously result from the generally different paces at which people complete assignments.. I was just raising one possible explanation, but it isn't something that should be changed. The reading assignments are a necessary part of the learning process.