Forum Discussion
Moving Average
Hi,
I've just started using PowerBI and I'm a massive fan of the tool. I've been trying to calculate a simple moving average for Months vs Sessions.
I've tried quite a lot of things, googling, etc for a few hours right now and I've read and tried to apply this link (http://community.powerbi.com/t5/Developer/How-to-calculate-Moving-Average-based-on-a-Rolling-10-hours/td-p/13332); but everytime I input and edit to my means I receive the errors;
-Can't resolve a valid name.
-Something like "can't find row being referred to".
I've tried creating it as a measure, as a column, decomposing the equation into multiple columns/functions, etc. I am at a bit of a wall and I would greatly apprecaite any help.
It's google analytics data so it looks roughly like this:
| Month of the Year | Sessions |
| 1 | 100 |
| 2 | 150 |
| 3 | 200 |
| 4 | 250 |
| 5 | 300 |
| 6 | 350 |
| 7 | 400 |
| 8 | 450 |
| 9 | 500 |
| 10 | 550 |
| 11 | 600 |
| 12 | 650 |
I'm quite comfortable transforming and shaping the data in excel, but I would really like to be able to shape my data in powerbi as it seems I've just misunderstood how to apply a dax expression as opposed to do all my data transformation in excel and then simply importing.
Any help would be much appreciated.
Firstly you need a column of date with full date format. Then you can use calculated measure to get the expected result. Please refer to following steps.
- Create a calculated column for the date.
FullDate = DATE ( 2016, 'Session'[Month of the Year], 1 )
- Create a measure for 3 months moving average. You can change the number of months if you want.
Moving_Average_3_Months = CALCULATE ( AVERAGEX ( 'Session', 'Session'[Sessions] ), DATESINPERIOD ( 'Session'[FullDate], LASTDATE ( 'Session'[FullDate] ), -3, MONTH ) ) - Drag the Line Chart into your canvas as below.
- Create a calculated column for the date.
30 Replies
There are a lot of foundational things you should do.
1. Set up a calendar table. Read my article about that here http://exceleratorbi.com.au/power-pivot-calendar-tables/
2. Join the data table to the calendar table. Read about data shape here http://exceleratorbi.com.au/the-optimal-shape-for-power-pivot-data/
A moving average would then normally use a measure (not calc column) something like this
Total Sales rolling quarter :=
CALCULATE (
Sum(data[qty]),
FILTER (
ALL ( Calendar ),
Calendar[MonthID] >= MAX (calendar[MonthID]) -2
&& Calendar[MonthID] <= MAX ( Calendar[MonthID] )
)
)There is a lot to learn if you want to understand it :-)
btw, your data looks like a running total, not a monthly qty, so you may need something different.
Dear Matt, i though that since time intelligence functions implemented in DAX calendar tables are not necessary anymore
I'm not sure what you mean. You definitely need a calendars table if you want to use the inbuilt time intelligence functions.
Hi, how can this be calculated if there are duplicate dates?
I have a DateTime column which has values for different timestamps on the same date. All the values are to considered while calculating the Average.
Hi all,
Very useful. However I'm still getting incorrect results in my model. For convenience I have renamed my data in accordance with the exmple in this thread.
I have multiple values per each date so my rolling average is too low, I need to calculated it based on the total for each date not based on the each value within the date.
Any suggestions
many thanks
Hi,
I would recommend to read this article.
Basically you need to create a period table containing all the dates in your data set and then connect your table with your values to this period table. The article talk about marking your table as a period table - this is not needed in Power BI it's only needed in Power Pivot for Excel. There is many awesome articles about how you can create a period table in Power BI - I like this one.
If you only have a month value in your values table then you need to convert this into a date to be able to create the relationship from this table to your period table - just pick the first day of the month.
Hey,
I really appreciate the responeses especially so quickly.
I'm not looking to do anything with Pivottable tbh, I might be missing something; but I was hoping for some direction in terms of DAX transforming data within PowerBI.
The links are in part useful in that they allow me understand a little bit and different approach to filtering the data.
I grabbed dates from analytics, set them as dates, but so I can try the datesbetween approach, but I'm still not sure and I'm unable to get past the error values.
I'm going to spend some time tonight reading upon on dax and creating formulas. Any help would be greatly appreciated!
Firstly you need a column of date with full date format. Then you can use calculated measure to get the expected result. Please refer to following steps.
- Create a calculated column for the date.
FullDate = DATE ( 2016, 'Session'[Month of the Year], 1 )
- Create a measure for 3 months moving average. You can change the number of months if you want.
Moving_Average_3_Months = CALCULATE ( AVERAGEX ( 'Session', 'Session'[Sessions] ), DATESINPERIOD ( 'Session'[FullDate], LASTDATE ( 'Session'[FullDate] ), -3, MONTH ) ) - Drag the Line Chart into your canvas as below.
Thank you so much for the responses.
v-sihou-msft Thank you so much.
sdjensen I took your advice and looked into creating its own date table, extremely useful!
I used this code to create a 10 day Simple Moving average:
Moving_Average_3_Months = CALCULATE ( AVERAGEX ( 'All Web Site Data', 'All Web Site Data'[Sessions] ), DATESINPERIOD ( 'Table123'[DateKey], LASTDATE ( 'Table123'[DateKey] ), -10, DAY ) )Link: https://gyazo.com/bb02f6541c6f0e99c4477f6b4ead42cd
The drill down feature doesn't seem to want to work for me. Should I simple create my own hierarchy for this?
- Create a calculated column for the date.
Thanks bro. It worked
