Weekly % Change DAX Formula Help

[ll0606]

Hello,

I have a Power BI dashboard and I am trying to determine what is the % change from one week to the next. I have a Date Table and have created a relationship between the Date Table and the Date in my file and that works great.  

This is what I currently have. You will see it is a breakdown for different file sizes week over week beginning on 1/1/2024 through 4/8/2024.  I need to know the percentage change difference from one week to the next and display it like the "%Weekly Change" row you see. But the percentages you see are all incorrect and is just there as a placeholder.  

For example, the week of 1/1/2024 shows total rows of 243,419 the next week of 1/8/2024 shows total rows of 242,254. I need a DAX measure/formula that will help me calculate what was the percentage of change between the number of rows from the previous week to the current week. Each week starts on a Monday.  I will need this measure to continue throughout the rest of 2024, 2025, etc.  Is anyone able to help me figure this out? I appreciate any assistance I can get.

[v-jiewu-msft · Accepted solution]

Hi @ll0606 ,

Based on my testing, please try the following methods:

1.Create the sample table.

2.Create the measure to calculate the change between the previous week and current week.

weekly change = 
var date_ = SELECTEDVALUE('Table'[Date])
VAR current_sum =
CALCULATE (
        SUM ( 'Table'[Number]),
        FILTER(ALL('Table'), 'Table'[Date] = date_)
    )

VAR sum_preWeek =
CALCULATE (
        SUM ( 'Table'[Number]),
        FILTER(ALL('Table'), 'Table'[Date] = date_ - 7)
    )

VAR min_week = 
    CALCULATE(MIN('Table'[Date]), ALLSELECTED('Table'[Date]))
RETURN
IF(date_ = min_week, BLANK(), DIVIDE((current_sum - sum_preWeek ), sum_preWeek))

3.Drag the measure into the matrix visual. Change the data Format.

4.The result is shown below.

Best Regards,

Wisdom Wu

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