Let’s say you are the people manager at ACME Inc. You are looking staff list for the months – January and February 2017. You see that we had 4,000 employees in Jan and 4,200 employees in Feb. So what is the churn?
- Is it just 200?
- Or is it the sum of people who left and who joined?
- What if you want to find out how many people moved to new designations / departments or groups?
You see, churn is tricky to figure out.
So why not invite the pros? ie Power Query.
Side note: You could also calculate churn in Excel (using formulas) or in SQL (by using long queries and unions with a boat load of joins)
Setting up your data – Churn analysis
The first step is to set up two sets of data (one for each point in time). Make sure that you include only relevant columns. Let’s say we go with below layout.
For the sake of simplicity, let’s call these tables thismonth and lastmonth. You can include the data date columns, but they are not necessary for the analysis.
Define churn
We can categorize churn in to one of these 6 levels.
- New employees
- Exits
- People who moved to a new group
- People who moved to a new branch
- People who moved to a new designation
- No changes
Figuring out the churn – Power Query
Here is the process to calculate the churn using Power Query.
- We create a third query by merging two datasets (thismonth and lastmonth) on employee number as Full Outer join (think of this as A union B in sets – ie any employee present in either months will be included)
- We define a custom column in this new query, called status. It will have
- New employees if emp number is null in last month’s column
- Exit if emp number is null in this month’s column
- New group if thismonth.group <> lastmonth.group
- New Branch if thismonth.branch <> lastmonth.branch
- New Designation if thismonth.designation <> lastmonth.designation
- No changes else
- We delete all rows with no changes (as we are only interested in churn)
- Load this data to Excel
Figuring out employee churn – Power Query lesson video
Since the process is somewhat technical and confusing, I made a video explaining everything in detail. Check it out below.
You can watch this video on our youtube channel too.
Download Example Workbook
Click here to download example workbook. You must have Power Query 2013 or Excel 2016 to customize anything.
More on Power Query
Power Query is awesome. If you haven’t explored its power, check out below tutorials and get started.
- Introduction to Power Query
- Unpivot data quickly with Power Query
- How to import web data to Excel using Power Query
- Recommended training: Power Query by Ken Puls
How do you calculate churn?
As mentioned earlier, we can use either Excel formulas or SQL to calculate churn. If I am only interested in high-level churn (ie entries and exits), I use a simple formula. But for anything more than that, I prefer Power Query or SQL (as PQ is not be available in all versions of Excel)
What about you? How do you calculate and analyze churn? Please share your approach and tips in the comments.
10 Responses to “Multiple Find Replace with Power Query List.Accumulate()”
Note: The text-formula above miss a -1. The video is correct.
😀 sorry, I made the exact same mistake as you did - initially - in the video. {0..3} is one thing, and Table.RowCount(replacements) -->3 items ={0,1,2} is another thing.
1st question : you've created a new column to put the replacements in. how ca we replace in the original column without creating a new one ?
2nd question : how can we replace the value in the entire cell and not only the text (Using ReplaceValue instead of text.Replace) ?
Thanks you in advance
Chandoo, I would be very interested to have your answers in both Yassine's questions!
Thank you for sharing,
Vassilis
Thank you for this! I was just doing an assignment where I was having to replace words with other words in my Excel sheet. We are starting with the basics in my class, so I know I don't have a huge list that I would need to find and replace, but this is something that could be useful down the road for me!
Hi
This is nearly perfect for my needs thank you, however I would like just the "replace" to be the result if possible please, I have tried in vain adjusting the formula without success.
Thank you in advance
Thank you! Awesome tip, and very flexible, too.
My find/replace values were in non-adjacent columns of a table containing a bunch of other data. Worked prefectly and I am now a tiny bit less clueless.
Hi!!!
I have the same question that Yassine did.
I need to replace the values in the same column. I don't want to create a new column e then have to remove the old column.
How could I could that?
That's a real fun article. It inspired me to delve deeper into the topic of List.Accumulate. I can see how the function works, but it takes an additional step to imagine how one can use it for more complex applications.
Your example also made it into my article, together with some other use-cases. Would be great to get your opinion on which other areas you would include in the article.
Let me drop the link to the page so others can too find it for further reading: https://gorilla.bi/power-query/list-accumulate/
Expression.Error: The name 'replacements' wasn't recognized. Make sure it's spelled correctly.