Average on weeklevel

Hey there! So, if you want to calculate the average costs per week, and you already have costs per day, you can use the DAX formula provided by AlB. The formula he gave you, CALCULATE( AVERAGE(Table1[Costs]), ALL(Table1[Datum]) ), will give you the average costs for the entire table, regardless of the date filter applied. This is because the ALL function removes any filters on the Datum column.

However, if you're saying that when you filter to a specific day, like 3-9-2019, and the cost for that day is 340 euros, then the average also shows 340 euros, it's because the filter context is affecting the calculation. When you filter to a specific day, the average is being calculated only for that day, hence you get the same value as the cost for that day.

To get the average costs for the entire week, even when you filter to a specific day, you need to modify the formula to ignore the day filter but respect the week filter. You can achieve this by using the ALLEXCEPT function. The formula would look something like this:

Measure = CALCULATE( AVERAGE(Table1[Costs]), ALLEXCEPT(Table1, Table1[Week]) )

With this formula, when you filter to a specific day, it will still give you the average costs for the entire week of that day. Hope this helps! If you have any other questions or need further clarification, just let me know!