The legend should probably be open by default. It is kinda annoying to keep referring to it, and it hides away in two seconds :) I also agree that this kind of

The legend should probably be open by default. It is kinda annoying to keep referring to it, and it hides away in two seconds :) I also agree that this kind of visualization is better served with having an animation, and an ability to select specific points in the timeline. I like the small multiples visualization, but the individual map view could be better. I'd also like to add that having the year show up on hover only is another pain-point. It should be rendered below each map as well.