I would like to have a yearly calendar view of my agenda. The code from https://stackoverflow.com/questions/9547912/emacs-calendar-show-more-than-3-months shows how to display a calendar for the whole year. Ideally, I would like to connect it to my agenda such as to color the background of each day according to the number of events for this day. This would allow me to quickly visually check what are the busy days (I imagine I can probably query the information but I would prefer such a visual). Is there any package that could do that?