Marco Russo and Alberto Ferrari work in weeks:
Weekly calendars are common in manufacturing, retail, and any business that is sensitive to weekends or to the number of working days. For example, the scenario described in this article uses the number of pageviews on a website from 2019 to 2024, with data available until September 3, 2024. The website analyzed has a clear weekly trend, with slower traffic over the weekend, as shown in the following line chart with a daily granularity. It seems like a business website. A sports website would probably display the opposite trend.
Read on to see some of the challenges around week-based calendars. There’s a reason I have a “Dates and Numbers” category on Curated SQL and it’s exactly for things like this: some of the most common things we as humans work with are extremely complex and fraught with exceptions, including calendars.