Previous function employee

ok i got you

you needed to be partitioned by pperson_bk

step0 : 

you need to fix the column functionchangedate to respect the following format : 

m-dd-yyyy

step1 :  go to power query and change the column functionchangeddate type from text to date 

step 3 : in power query sort asc the first column : 

step 4 :  

sort functionchangeddate column asc  

save and apply. 

step 5 : 
use this measure now : 

Column =

var current_perosn = 'Table (7)'[Person_BK]

var current_date = 'Table (7)'[FunctionChangedDate]

var datasource =

    FILTER(

        all('Table (7)'[FunctionChangedDate],'Table (7)'[FunctionName],'Table (7)'[Person_BK]),

        'Table (7)'[Person_BK] = current_perosn && 'Table (7)'[FunctionChangedDate] <=current_date

        && 'Table (7)'[FunctionChangedDate] <=current_date

        )

return  

SELECTCOLUMNS(

offset(

    -1,

    datasource,

    ORDERBY('Table (7)'[FunctionChangedDate] , asc ),

    PARTITIONBY('Table (7)'[Person_BK])

),

[FunctionName]

)