# Comparing New vs Lost vs Steady Customers over Multiple Years - Customer Churn Examples - Advanced DAX

It’s absolutely making sense, Sam but when I used your formulas of 23rd of March in my example-file it seems to be correct. When I put these formulas in data from 2003 until 2018 I’ve got some differences in the calculations.

The calculation
New Customers Total (old) -/- Lost Customers +/+ New Customers Total = New Customers Total (new)
wasn’t correct.
The reason for this was the return of some customers. We’ve counted them as lost but they returned.

Also the following calculation of the Sales was incorrect:
Total Sales (old) -/- Customer Revenue Lost -/- Lost Sales Steady +/+ Won Sales Steady +/+ New Customer Sales = Total Sales (new)

The reason for this was the same, the difference was the sales of the returning customers.

I’m a Finance-man, is it possible to make the numbers correct? Maybe we have to change some formulas of the 23rd of March? Or do I have to accept the differences?

With kind regards,

Cor

This formula here also looks one year forward also to see if customer came back. But it only looks one year forward.

Does this get you what you need?

``````Customer Lost =
VAR CustomersTY = VALUES( Invoices[Customer] )
VAR CustomerLY = CALCULATETABLE( VALUES( Invoices[Customer] ), SAMEPERIODLASTYEAR( 'Calendar'[Date] ) )
VAR CustomerFuture = CALCULATETABLE( VALUES( Invoices[Customer] ), DATEADD( 'Calendar'[Date], 1, YEAR ) )

RETURN
IF( ISBLANK( [Customer Sales TY] ),
BLANK(),
COUNTROWS( EXCEPT(
EXCEPT( CustomerLY, CustomersTY ),
CustomerFuture ) ) * -1 )
``````

Hi Sam, thanks for you new formula!

Next week I will try this formula with the data from 2003-2018 and I will let you know what the results are.

Have a nice weekend!

Regards,

Cor

Hi Sam, your formula is working on the dummy data but, unfortunately, isn’t the solution for the data from 2003 until 2018. I think that I have to accept the differences. There are too many ways we’ve invoiced our customers and it isn’t possible to make different measures for every exception.

I would like to thank you for the many DAX-lessons and I’m looking forward to speak to you for a next challenge.

With kind regards,

Cor

Ok thanks for letting me know

Hi Sam,

Can you help me with another churn-question…?

Instead of a yearly churn-comparison our company wants a quarterly comparison:

Additional information: this is dummy data en LTM means “Last Twelve Months”.

How do I have to change the formulas for the new - lost and steady customers?

For the totals of the dummy data I have

``````Total Customers LTM =
CALCULATE(DISTINCTCOUNT(Invoices[Customer]);
DATESBETWEEN('Calendar'[Date];
NEXTDAY(SAMEPERIODLASTYEAR(LASTDATE('Calendar'[Date])));
LASTDATE('Calendar'[Date])))
``````

With kind regards,

Cor

The dummy data I’ve used:

Customer Invoice Invoice_Date Year_Invoice Amount_Excl_VAT YMD-key
1 1001 1-3-2014 2014 25 20140301
2 1002 5-6-2014 2014 40 20140605
3 1003 9-9-2014 2014 35 20140909
4 1004 10-12-2014 2014 12 20141210
1 1005 1-4-2015 2015 45 20150401
2 1006 3-3-2015 2015 38 20150303
3 1007 2-2-2015 2015 27 20150202
5 1008 4-6-2015 2015 30 20150604
6 1009 2-8-2015 2015 60 20150802
7 1010 7-7-2015 2015 40 20150707
8 1011 15-10-2015 2015 35 20151015
1 1012 21-2-2016 2016 73 20160221
2 1013 7-11-2016 2016 45 20161107
5 1014 15-7-2016 2016 60 20160715
6 1015 2-4-2016 2016 60 20160402
7 1016 28-8-2016 2016 38 20160828
9 1017 14-1-2016 2016 10 20160114
10 1018 8-11-2016 2016 15 20161108
11 1019 25-11-2016 2016 27 20161125
1 1020 1-4-2017 2017 98 20170401
5 1021 23-2-2017 2017 58 20170223
7 1022 8-12-2017 2017 36 20171208
9 1023 24-12-2017 2017 20 20171224
10 1024 6-6-2017 2017 12 20170606
11 1025 1-6-2017 2017 27 20170601
12 1026 8-6-2017 2017 25 20170608

Hi Cor,

Another tough one here.

Can you add the Power BI model here. Just going to require some testing I think.

I just want to be able to see exactly how this is going to be represented and then run some formula testing through it.

Thanks

bi2-207 churn analysis new-steady-lost customers.pbix (219.3 KB)
Hi Sam,

See attachment for the dummy data.

Chrs,

Cor

Hi Cor, sorry for the delay

Have you by chance reviewed this resource here?

This has basically the formula pattern to use for quarterly churn calculations

Here’s a summary of it

``````New Customers 90 days =
VAR CustomerTM = VALUES( Sales[Customer ID] )
VAR PriorCustomers = CALCULATETABLE( VALUES( Sales[Customer ID] ),
FILTER( ALL( Dates ),
Dates[Date] > MIN( Dates[Date] ) - 90 &&
Dates[Date] < MIN( Dates[Date] ) ) )

RETURN
COUNTROWS(
EXCEPT( CustomerTM, PriorCustomers ) )
``````

That’s quite a detailed workshop as well

See here for lost customers as well

``````Lost Customers =
VAR CustomersPurchased = CALCULATETABLE( VALUES( Sales[Customer ID] ),
FILTER( ALL( Dates ),
Dates[Date] >  MIN( Dates[Date] ) - 365 &&
Dates[Date] <=  MIN( Dates[Date] ) - 90 ) )
VAR PriorCustomers = CALCULATETABLE( VALUES( Sales[Customer ID] ),
FILTER( ALL( Dates ),
Dates[Date] >  MAX( Dates[Date] ) - 90 &&
Dates[Date] <= MAX( Dates[Date] ) ) )
RETURN
COUNTROWS( EXCEPT( CustomersPurchased,  PriorCustomers ) ) * -1
``````

Understanding CALCULATETABLE is key here

See how you go with these

Hi Sam,

Sorry for the delay, it is holiday-time in The Netherlands and I wasn’t able to access the materials.
I saw both of the videos you’ve mentioned and the techniques are more clear to me than before.
After the holidays I will dive deeper into the quarterly comparisons.

I’ve a question about the new customers and the new customer sales.
The formulas:

``````New Customers =
VAR CustomerTM = VALUES( Sales[Customer ID] )
VAR PriorCustomers = CALCULATETABLE( VALUES( Sales[Customer ID] );
FILTER( ALL( Dates );
Dates[Date] > MIN( Dates[Date] ) - [Churn Time Frame Value] &&
Dates[Date] < MIN( Dates[Date] ) ) )

RETURN
COUNTROWS(
EXCEPT( CustomerTM; PriorCustomers ) )

New Customer Sales =
VAR CustomerTM = VALUES( Sales[Customer ID] )
VAR PriorCustomers = CALCULATETABLE( VALUES( Sales[Customer ID] );
FILTER( ALL( Dates[Date] );
Dates[Date] > MIN( Dates[Date] ) - [Churn Time Frame Value] &&
Dates[Date] <= MIN( Dates[Date] ) ) )

RETURN
CALCULATE( [Total Sales];
EXCEPT( CustomerTM; PriorCustomers ) )
``````

In the first you’ve used the part “Dates[Date] < MIN( Dates[Date]”, in the second you’ve used the part “Dates[Date] < = MIN( Dates[Date]”, why did you use in the second the extra “=”?

I will talk to you after the holidays,

Chrs,

Cor

I actually think the = is a small oversight. Don’t think you need it here.

Hi Sam,

I’m back from my holiday in Valencia-Spain and I’m struggling again with the formulas so please help me.
I want to compare different periods with each other, see photo below:

How can I put those periods in the different DAX-formulas? I understand the techniques of CALCULATETABLE, EXCEPT, INTERSECT etc. but I have some difficulties to put those periods into CALCULATETABLE.

Cor

Have you got a date table setup?

You will need one for using these formulas and to run this type of analysis.

You can use the date table code within all the course and resources that are made available.

You will just need to make sure your quarters column aligns with the correct dates, then you can just use these formula as is.

Let me know.

Sam

Yes, Sam, I have a date table but I am struggling with the formula.

Won Customers LTM =
VAR CustomerLTM = CALCULATE(DISTINCTCOUNT(Invoices[Customer]);
FILTER(ALL(‘Calendar’);
** what do I have to put here?**
VAR PriorCustomers = CALCULATE(DISTINCTCOUNT(Invoices[Customer]);
FILTER(ALL(‘Calendar’ );
** what do I have to put here?
RETURN
COUNTROWS(
EXCEPT(CustomerLTM; PriorCustomers ) )
))

Can you help me?

Cor

For the CustomerLTM seems to me that
DATESBETWEEN (
Calendar[FullDate],
NEXTDAY ( SAMEPERIODLASTYEAR ( LASTDATE ( Calendar[FullDate] ) ) ),
LASTDATE ( Calendar[FullDate] )
)
is the part that I missed but what do I have to use for the PriorCustomers?

I think I’ve found it:

``````Won Customers LTM =
VAR CustomerLTM = CALCULATETABLE(VALUES(Invoices[Customer]);
DATESBETWEEN ('Calendar'[Date];
NEXTDAY ( SAMEPERIODLASTYEAR ( LASTDATE ( 'Calendar'[Date] ) ) );
LASTDATE ( 'Calendar'[Date] )))
VAR PriorCustomers = CALCULATETABLE(VALUES(Invoices[Customer]);
DATESBETWEEN('Calendar'[Date];
RETURN
COUNTROWS(
EXCEPT(CustomerLTM;PriorCustomers))``````

Ok yep that’s great. Yes, I think you certainly have the idea now.

Some sort of pattern but just slight adjustment required for the context of the calculation like you have done.

Chrs, Sam

Hi Sam,

See attachment.

I am looking for a correct formula for Won Clients for 2004-2.
The context is Year-Month and the comparison is the number of customers last 12 months with the number of customers last 12 month for the prior month.

The correct answer for periode 2004-2 is 356 customers and I have made 3 different measures and the results of these 3 measures is 384 customers. I’m doing something wrong but I don’t know what. Maybe is the reason the leapday 29-02? Can you help me with the correct formula?

Another question:
Result 2003-1: the Total Clients Prior Period -1M and Lost Clients LTM give a result. What can I do to get rid of these results?

Chrs, Cor

Check this one out

``````Won3 Clients LTM =
VAR CustomerLTM = CALCULATETABLE(VALUES('2003-2004 Invoices'[Customer]),
DATESBETWEEN ('Calendar'[Date],
NEXTDAY ( SAMEPERIODLASTYEAR ( LASTDATE ( 'Calendar'[Date] ) ) ),
LASTDATE ( 'Calendar'[Date] )))
VAR PriorCustomers = CALCULATETABLE(VALUES('2003-2004 Invoices'[Customer]),
DATESBETWEEN('Calendar'[Date],
RETURN
COUNTROWS(
EXCEPT(CustomerLTM,PriorCustomers))
``````

The original formula wasn’t actually finding the last date in January, it was going to the 29th

I just tested it (and that’s what I’ve circled). So I knew that wasn’t what you wanted.

You’ll see in the below formula I’ve adjusted it a little bit.

I always break things down like this to audit. It’s the best way.

Chrs