Power BI Retrieve Last Column Value by Group

Question

I'm working in a dashboard that control some kpis at my company. Now, I need to compare every result with the previous one, according to employee number. In the sample below, I show a little exemple of my data, and the expected result in the last column (previous score). I've tryed to solve that using a lot os calculated columns. I got close using the following:

PreviousScore = 
VAR EMPNUMBER = BASE[Employee Number]
VAR REF = BASE[Score]

RETURN
CALCULATE(LASTNONBLANK(BASE[Employee Number];EMPNUMBER);FILTER(BASE;BASE[Employee Number]=EMPNUMBER);FILTER(BASE;BASE[Date]<EARLIER(BASE[Date])))

Employee Number Date Score Previous score

1234 01/01/2019 1 BLANK

1235 01/01/2019 4 BLANK

1236 01/01/2019 2 BLANK

1288 01/01/2019 0 BLANK

1259 01/01/2019 0 BLANK

1234 01/02/2019 3 1

1235 01/02/2019 4 4

1236 01/02/2019 1 2

1288 01/02/2019 2 0

1259 01/02/2019 4 0

1234 01/03/2019 1 3

1235 01/03/2019 2 4

1236 01/03/2019 3 1

1288 01/03/2019 0 2

1259 01/03/2019 1 4

1234 01/04/2019 2 1

1235 01/04/2019 3 2

1236 01/04/2019 8 3

1288 01/04/2019 BLANK 0

1259 01/04/2019 BLANK 1

I hope someone could help with this issue.

LW

Answer 1

You have no dependance between your dates, you pickup the earlier column and by accident they are in the right order.

The following query will give you the right result:

Previous score = 
    var empNR = score[Employee Number]
    var theDate = score[Date]
    var empData = FILTER(score;score[Employee Number] = empNR)
    var prevDate = CALCULATE(MAX(score[Date]);empData;score[Date] < theDate)
    return CALCULATE(MAX(score[Score]);FILTER(empData; score[Date] = prevDate))

1. I filter on emp number to get the data of that employee
2. I get the prevDate by getting the max of all dates which are lower than selected date
3. last step is to get the one row and return the score