Calculate Running Average Using DAX in Power BI - powerbi

Question

I have the following values in Table_1:
date sales_amount
04/01/2021 100.00
04/02/2021 300.00
04/05/2021 500.00
I want to compute a running average, so the average is computed as each day passes, so that my final output looks like this:
date sales_amount running_average
04/01/2021 100.00 100.00
04/02/2021 300.00 200.00
04/05/2021 500.00 300.00
The sales person did not work on 04/03 and 04/04, so I want to exclude them from my running average.
Right now, my output looks like this, which is wrong for what I am doing:
date sales_amount running_average
04/01/2021 100.00 100.00
04/02/2021 300.00 200.00
04/05/2021 500.00 180.00
Any suggestions?
Right now, my DAX code looks like this:
test_new =
VAR LastVisibleDate = MAX('Table_1'[Date])
VAR FirstVisibleDate = MIN('Table_1'[Date])
VAR LastDateWithSales =
CALCULATE(
MAX('Table_1'[Date]),
REMOVEFILTERS()
)
VAR Result =
IF (
FirstVisibleDate <= LastDateWithSales,
CALCULATE(
AVERAGE([Sales_Amount]),
Table_1[Date]
)
)
RETURN
Result

Answer 1

I have added a few lines in the last variable:
Table_1[Date] in the last variable basically means FILTER ( ALL ( Table_1[Date] ), TRUE ), and that will return all of the dates so not useful in your scenario as it will give wrong results, instead write Table_1[Date] <= LastVisibleDate
You don't need REMOVEFILTERS when you have Date column coming from the Dates table and the Date table is marked as a Date table because when a date table is marked as a date table the engine automatically adds a REMOVEFILTERS/ALL whenever a filter is applied over the Date column, but that won't happen with Date column of other tables hence you need to write an explicit REMOVEFILTERS in the last variable
test_new =
VAR LastVisibleDate =
MAX ( 'Table_1'[Date] )
VAR FirstVisibleDate =
MIN ( 'Table_1'[Date] )
VAR LastDateWithSales =
CALCULATE (
MAX ( 'Table_1'[Date] ),
REMOVEFILTERS ()
)
VAR Result =
IF (
FirstVisibleDate <= LastDateWithSales,
CALCULATE (
AVERAGE ( [Sales_Amount] ),
Table_1[Date] <= LastVisibleDate,
REMOVEFILTERS ( Table_1 )
)
)
RETURN
Result
As a best practice always use Date column from a Date table.