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ScORE
Helper I
Helper I

Calculate number of weeks, if date blank automatically calculate from a different date

Calculate number of wees between 2 dates. If a date is blank use 1/1/2017

 [ New ] 
 
 

Hello all,

 

I need help calculating the number of weeks between 2 columns.  The challenge is one of the columns may be blank at times.  If they are blank i'd like to the formula to use another date automatically.  For the purposes pf this example I have the following columns:

 

Start Date  End Date  # of weeks (need help calculating)
1/1/20175/5/2017 
2/2/20175/5/2017 
6/20/20175/5/2017 
4/15/20175/5/2017 
 5/5/2017 
1/1/2017  5/5/2017 
   
1/1/20175/5/2017 
1/1/2017  
 5/5/2017 
   

 

 

- If the start date is missing, I'd like to use the beginning of the year (1/1/2017) as the start date to calculate the number of weeks.

- If the end date is missing, I'd like to use the current date (today) for the end date.  

- If both dates are present, I'd like to use those dates as is.  

- I will be summing the number of weeks to across different regions and groups to show the total number of weeks active.

 

 

I'm not sure if this is a measurement or if I need to add a column.  I'll be using this rolled up at different levels of  a hierarchy and need to calculations to adjust based on the what the user is filtering by.

 

Any help on this is greatly appreciated.  

ScORE

1 ACCEPTED SOLUTION
Zubair_Muhammad
Community Champion
Community Champion

Hi @ScORE

 

Try this calculated column

# of weeks =
VAR alternateStartDate =
    DATE ( 2017, 1, 1 )
VAR alternateEndDate =
    TODAY ()
RETURN
    DATEDIFF (
        IF ( ISBLANK ( Table1[Start Date] ), alternateStartDate, Table1[Start Date] ),
        IF ( ISBLANK ( Table1[End Date] ), alternateEndDate, Table1[End Date] ),
        WEEK
    )

View solution in original post

5 REPLIES 5
v-ljerr-msft
Microsoft Employee
Microsoft Employee

Hi @ScORE,

 

Have you tried the solutions provided above? Do they work in your scenario? If some solution works, could you accept it as solution to close this thread?

 

If you still have any question on this issue, feel free to post here. Smiley Happy

 

Regards

Zubair_Muhammad
Community Champion
Community Champion

Hi @ScORE

 

Try this calculated column

# of weeks =
VAR alternateStartDate =
    DATE ( 2017, 1, 1 )
VAR alternateEndDate =
    TODAY ()
RETURN
    DATEDIFF (
        IF ( ISBLANK ( Table1[Start Date] ), alternateStartDate, Table1[Start Date] ),
        IF ( ISBLANK ( Table1[End Date] ), alternateEndDate, Table1[End Date] ),
        WEEK
    )

Thank you!  This worked and is giving me what I need.  The only problem isthe tables are ommitting instances where there should be data; not pulling everything in.  

jthomson
Solution Sage
Solution Sage

Probably a few ways to do this - one would be to alter the data in Power Query, so that you fill in the blanks with your desired alternative outcomes, the other would be to create a couple of measures so that you have something like:

 

FixedStartDate = if([StartDate]=null, 01/01/2017, [StartDate])

FixedEndDate = if([EndDate]=null, TODAY(), [EndDate])

 

Syntax might not be exactly right, but it should give you a starting point - you can then take one away from the other and then multiply by 1/7 to get the number of weeks

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