Rolling average a certain period using a DAX measure in Power BI - postgresql

Question

I tried generating a DAX measure as a rolling average. I don't quite know how to insert the measure I need rolling averaged as "CPI_annualized". It is not giving an option to bring CPI_annualized into the Rolling Average calc.
This is the error I am given when trying to construct the RollingAverage VAR in the measure P_MA
The syntax for 'CALCULATE' is incorrect. DAX(VAR __LAST_DATE = LASTDATE('public econometrics'[date]) ......
This is the DAX measure that I am trying to complete :
P_MA =
VAR __NUM_PERIODS = 3
VAR __LAST_DATE = LASTDATE('public econometrics'[date])
VAR RollingAverage =
AVERAGEX(
DATESBETWEEN(
'public econometrics'[date],
DATEADD(__LAST_DATE, -__NUM_PERIODS, MONTH),
__LAST_DATE)
CALCULATE([CPILFESL]))
)
RETURN RollingAverage
This is the DAX measure that I am trying to use in the rolling calculation with the data in my dB given monthly. This works as below.
CPI_annualized = (CALCULATE(SUM('public econometrics'[value]),'public
econometrics'[econometric_name]=="CPILFESL")/CALCULATE(SUM('public
econometrics'[value]),'public
econometrics'[econometric_name]=="CPILFESL",SAMEPERIODLASTYEAR('public econometrics'[date])))-1
Inserting this measure in a line chart gives my this table.
date
CPILFESL
1 January, 1978
6.41%
1 February, 1978
6.20%

Answer 1

I think you are getting error message due to this line:
CALCULATE([CPILFESL])
In Dax Calculate measure, you cannot directly calculate a value, instead you have to include a number calculation function such as sum, max, min, here is the example:
CALCULATE(sum([CPILFESL]))
In addition, you can get rid of Calculate measure when there is no filter expression, such as sum([CPILFESL]) is enough.
A proper way of using calculate is to filter the value, as shown in online documentation
CALCULATE(
SUM(Sales[Sales Amount]),
'Product'[Color] = "Blue"
)

Answer 2

You can find many usefull templated here:
https://www.daxpatterns.com/month-related-calculations/
Moving average 3 months
VAR MonthsInRange = 3
VAR LastMonthRange =
MAX ( 'Date'[Year Month Number] )
VAR FirstMonthRange =
LastMonthRange - MonthsInRange + 1
VAR Period3M =
FILTER (
ALL ( 'Date'[Year Month Number] ),
'Date'[Year Month Number] >= FirstMonthRange
&& 'Date'[Year Month Number] <= LastMonthRange
)
VAR Result =
IF (
COUNTROWS ( Period3M ) >= MonthsInRange,
CALCULATE (
AVERAGEX ( Period3M, [Sales Amount] ),
REMOVEFILTERS ( 'Date' )
)
)
RETURN
Result