OPENINGBALANCEWEEK
An expression evaluated at the last date of the week before the filter context's; needs a calendar.
Part of the calendar-based time intelligence that Power BI added in 2025.
Group: Time intelligence. Compatible with DAX.
Syntax
OPENINGBALANCEWEEK ( <expression>, <calendar> [, <filter>] )| Parameter | Type | Description |
|---|---|---|
expression | Expression | The value wanted on that one date, usually a measure of a level such as a price, a stock or a balance. |
calendar | Calendar | The name of a calendar defined in the model that has a week category. |
filter | Filter optional | A condition or a table that filters as well, as a filter argument of CALCULATE does. |
Returns
Same type as the expression. The expression on the calendar's last date before the week.
Remarks
- It takes a calendar only: a column of dates is an error. A calendar is defined in the model on a date table and tags its columns as year, quarter, month, week, date and the like; the week is whatever the calendar's week column says, ISO weeks from Monday or a retail week.
- The week is the one of the first date in the filter context; the result is the expression on the date just before that week starts. With ISO weeks and Wednesday 13 March 2024 in the filter, it reads Sunday 10 March.
- When the expression is blank on that date, the result is BLANK.
- The calendar must be able to read the filter context: one of weeks and dates without months cannot answer under a filter on a month, and the call is an error.
Examples
Without a calendar
The Example Brewery defines no calendar, so a date column is all it can offer, and the call fails.
EVALUATE
ROW ( "Opening", OPENINGBALANCEWEEK ( [Close price], Prices[Date] ) )Result: an error.
Related functions
CLOSINGBALANCEWEEK, OPENINGBALANCEMONTH, STARTOFWEEK, PREVIOUSWEEK.