For Christmas mail 2018, incoming and outgoing emails are presented in the form of lines, which - for each day with email traffic - create a small Christmas tree.
The larger the number of characters in the e-mails, the more branches there are and the larger the tree is. In the resulting "forest", the months are arranged one below the other according to the calendar. Each Christmas tree is assigned to the corresponding day.
Finally, the resulting data visualizations were put on paper this year by our pen plotter.