How to calculate how many weeks are left in the year based on a non date type column?

[vcm]

I am trying to calculate how many weeks are left in the year based on a column that concatenates year + week. Example, the column I'm trying to base the calculation looks like:

Week Start 

202515

202552

202602

Ideally, I would like a measure that would tell me the following,

Week Start  Weeks Left in the Year

202515        38

202552        1

202602        50

I'm having some trouble figuring this out since I'm not using a date type column and I would like it to dynamically update since it will have multiple years included in the data set. Any ideas on how I can get it done?

Thanks

[FreemanZ]

hi @vcm ,

try to write a measure like:

Weeks Left in Year = 
VAR TargetYear = LEFT(SELECTEDVALUE(data[Week Start]), 4)
VAR Jan1 = DATE(TargetYear,1,1)
VAR IsLeapYear =
    IF(
        (MOD(TargetYear, 4)=0
            && MOD(TargetYear,100)<>0)
        || MOD(TargetYear, 400)=0,
    TRUE, FALSE
    )
VAR Jan1Weekday = WEEKDAY(Jan1, 2)
VAR _Result =
    IF(
        Jan1Weekday=1 || (IsLeapYear && Jan1Weekday=7), 53, 52
    ) -
    RIGHT(MAX(data[Week Start]),2)
RETURN _Result

it worked like:

[djurecicK2 · Accepted solution]

Hi @vcm ,

 You could do something like this:

Weeks Left In Year = 52- RIGHT('Table'[Week Start],2)

[FreemanZ]

This might be an issue if there are 53 weeks in a year, like 2015, 2020. 

[vcm]

Agreed, it just works for my purposes since some other work is done to remedy it.

[rohit1991]

Hii @vcm 

Since your column is in YYYYWW format (year + week) and not a true date, you can extract the year and week number and calculate remaining weeks using a standard 52-week year. The logic is simply 52 minus the current week number, adjusted per year.

Weeks Left in Year =
VAR YearValue =
    INT ( SELECTEDVALUE ( 'Table'[Week Start] ) / 100 )
VAR WeekValue =
    MOD ( SELECTEDVALUE ( 'Table'[Week Start] ), 100 )
RETURN
    52 - WeekValue + 1