I have to think on this. I don’t know if it’s Chukas Aku”m. It represents something related to Avoda Zarah, but it definitely does serve a practical purpose (you need a calendar).
DY: Right, so that’s the issue. We’re okay with commemorating random milestones (birthdays, anniversaries, etc.). So is it Chukas Akkum to commemorate another year on the calendar? I’m leaning no, but I hear the Tzad to say yes.