Use previous row in current column calculation

[mellon199]

Hello, trying to create a calculated column using data from the previous row.

See example below for situation which has been calculated in excel for Indexation Factor.

Indexation factor formula = B2*(1+A3)

Within excel row B1 is manually set to 1 and the fields below are using the calculation above.

Can this be replicated using a calculated column within PowerBI? Thanks in advance.

(A) Selected Index	(B) Indexation Factor
	1
0.029683	1.029683334
0.004578	1.03439749
0.049629	1.08573384
0.047982	1.137829244
0.030898	1.172985656
0.028848	1.206823699
0.019598	1.230475107
0.010779	1.24373867
0.021425	1.270385647
0.037423	1.31792673
0.030566	1.358210528
0.025874	1.393353256
0.012128	1.410252314
0.057762	1.491711364
0.123262	1.675582498
0.043063	1.747738101

[tamerj1 · Accepted solution]

Hi @mellon199 
Here is a sample file with the solution https://we.tl/t-KyxjUgcvAi

For a caclulated column:

Indexation Factor = 
VAR T1 = 
    FILTER ( 
        Data, 
        Data[Index] <= EARLIER ( Data[Index] ) 
    )
RETURN
    PRODUCTX ( 
        T1,
        1 + Data[Selected Index]
    )

For a measure:

Indexation Factor Measure = 
VAR SelectedIndex = 
    SELECTEDVALUE ( Data[Index] )
VAR T1 = 
    CALCULATETABLE ( 
        Data, 
        Data[Index] <= SelectedIndex,
        ALL ( Data[Selected Index] )
    )
RETURN
    PRODUCTX ( 
        T1,
        1 + Data[Selected Index]
    )

[mellon199]

Amazing @tamerj1 - Thank you for taking the time to complete a working example!  😊

[Greg_Deckler]

@mellon199 See my article on Mean Time Between Failure (MTBF) which uses EARLIER: http://community.powerbi.com/t5/Community-Blog/Mean-Time-Between-Failure-MTBF-and-Power-BI/ba-p/3395....
The basic pattern is:
Column = 
  VAR __Current = [Value]
  VAR __PreviousDate = MAXX(FILTER('Table','Table'[Date] < EARLIER('Table'[Date])),[Date])

  VAR __Previous = MAXX(FILTER('Table',[Date]=__PreviousDate),[Value])
RETURN
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