There are some twist to keep in mind, when working with ISO calendar weeks. The first week of the year is defi
formular for ISO calendar week
Hint: The parameter 21 is not always documented for PowerBi depending on the source.
formular for ISO year
For grouping we need to know to which year a calendar week belongs. It could be that the last week lays in the new year but for aggregation purpose these week counts to the previous year.
formular for monday
Calculate the date of monday from iso week and year.
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