In any given year, there are 260 or 261 days in the year excluding weekends. This varies due to the fact that leap years have an extra day.
In non-leap years, this calculation process is simple. As there are 52.14 weeks in a year and two weekend days in each of them, simply multiply 52.14 by 5 to get 261 (when rounded up).
There are a number of reasons why this information would be useful, the most important of which is in determining the number of business days in a year. This is often an important component of planning a company’s calendar year. Obviously, this is particularly important for non-retail companies that work strictly on business days and never operate on weekends. It is important to note that this figure does not include the holidays and other breaks during the year. Companies that close on the weekends are unlikely to actually have 260 working days after accounting for holiday time and miscellaneous closings.
In leap years, there is one extra day on the calendar to consider, and this alters the math slightly. There are still two weekend days for each of the 52 weeks, but those 104 weekend days are subtracted from 366 days in this case. This creates an extra business day for leap years.