topic Re: new customers trend over time in App Development

new customers trend over time

agigliotti — Tue, 17 Mar 2026 14:40:07 GMT

Hello,
I'd need to create a bar chart with:

- year quarter on X axis (ex. Q1 2026)

- number of new customers on Y axis (as customers who bought in actual period and didn't in previous)

example:
for Q1 2026 the value of Y axis should be calculated as number of customers who bought in Q1 2026 and didn't in Q4 2025 and so on...

The end user should be able to filter by product/product category and any other filters in the UI.

Then it can't be pre calculated in the script.

Could you help me to find the best way to achieve it?
Many thanks in advance for your time.

Best Regards

Re: new customers trend over time

WeLoveQlik — Tue, 17 Mar 2026 11:45:43 GMT

Are you looking to compare to just the prior quarter or any prior quarter?

Meaning If I made a purchase 2 years ago, should I be counted as a new customer this quarter, or no?

Re: new customers trend over time

agigliotti — Tue, 17 Mar 2026 13:07:10 GMT

in this case only the prior quarter, but I'll need also comparing with the same quarter previous year.

Re: new customers trend over time

WeLoveQlik — Tue, 17 Mar 2026 13:31:58 GMT

I would do a check in the script.

First, load a distinct List of Customers and a Flag (I would use a 1) where Quarter = Prior Quarter.

Then, load a distinct list of Customers and a Flag where Quarter = Current Quarter.

Join the table together and if ISNULL(PriorQuarterCustomer) and CurrentQuarterCustomer >1 , New Customer, Existing Customer.

Each reload this check would be made and you should capture all new customers.

You could then use the New Customer flag in set analysis of your expressions.

Re: new customers trend over time

marcus_sommer — Tue, 17 Mar 2026 13:46:40 GMT

I could imagine that the simplest approach would be not to use year-quarter as dimension else using n expressions (for each bar one) because it decoupled the periods from each other. Defining the current and previous one within appropriate set statements is rather simple - but in regard to the relationship of the data the current ones doesn't belong to the previous ones and revers and therefore they couldn't be compared directly.

UI alternatives may be to wrap the comparing logic within (n) aggr() to implement there approaches which ignore/overwrite the relationship with set statements like {1} and/or using interrecord-functions like above() to connect different periods with each other. Depending on real scenario such method could become quite complex.

Personally I would tend to transfer the essential part of the logic into the data-model by using The As-Of Table - Qlik Community - 1466130 or creating (n) flags containing the offset between the sales in day/month/quarters and/or between the sales and today and maybe some kind of clustering/scoring of these flags.

Re: new customers trend over time

agigliotti — Tue, 17 Mar 2026 14:36:48 GMT

I forgot to say that the end user should be able to filter by product/product category and any other filters in the UI.
Then it can't be pre calculated in the script.

Re: new customers trend over time

WeLoveQlik — Tue, 17 Mar 2026 14:40:29 GMT

using Product as an example. If they select product A, do you want to know if the customer purchased that particular product as a new customer this quarter vs last or any product?

Re: new customers trend over time

agigliotti — Tue, 17 Mar 2026 14:47:03 GMT

If they select product A then Q1 2026 should be calculated as the number of customers that purchased that product in Q1 2026 but didn't in Q4 2025.

Re: new customers trend over time

WeLoveQlik — Tue, 17 Mar 2026 14:52:06 GMT

ok, great. It may take a little tweaking but something like this should work

Count(
If(
Sum({<YearQuarterIndex = {"$(vMaxQuarter)"}>} SalesAmount) > 0
AND
Sum({<YearQuarterIndex = {"$(vMaxQuarterM1)"}>} SalesAmount) = 0,
CustomerID
)
)

Your variables will have to ignore selections to ensure you are always getting the max quarter and Prior Quarter.

I suggest using an Index so at the turn of the year you can compare 2026Q1 and 2025Q4

Re: new customers trend over time

agigliotti — Tue, 17 Mar 2026 14:54:24 GMT

For the real scenario an UI approach is needed.
If it can be useful I can attach a small part of the fact table.

Re: new customers trend over time

agigliotti — Tue, 17 Mar 2026 14:59:28 GMT

I guess an Aggr() function is needed...nested aggregation not allowed.

Re: new customers trend over time

marcus_sommer — Tue, 17 Mar 2026 15:49:58 GMT

Yes, an aggr() will be needed to aggregate the results of the more granular conditions. Depending on the data-set it might not be necessary to sum the sales else just checking if any sales exists. It may look like:

sum(aggr(
-(count({< YQI = {$(=max(QYI)), $(=max(YQI)-1)}>} distinct YQI)=1),
CustomerID))

sum(aggr(
-(count({< YQI = {$(=max(QYI)-1), $(=max(YQI)-2)}>} distinct YQI)=1),
CustomerID))

... and so on - maybe 8 expressions to reflect the trend of two years - and the expression-labels are: max(QYI), max(QYI)-1 ....

ps. YQI = year(Date) * 4 + quarter(Date)

Re: new customers trend over time

agigliotti — Tue, 17 Mar 2026 16:31:02 GMT

if i well understood the bar chart will have 8 expressions to cover 2 years, one for each quarter ?

what about chart dimension?

Re: new customers trend over time

marcus_sommer — Tue, 17 Mar 2026 16:44:13 GMT

Each bar covers a quarter therefore no year-quarter or other period-information are needed respectively mustn't be applied.

Re: new customers trend over time

agigliotti — Tue, 17 Mar 2026 18:23:28 GMT

I was trying to go through Quarter as a chart dimension and using Aggr() e Above() functions in the expression but with no success.
I do think the only way to achieve it is using one expression for each time period with no time dimensions.

Re: new customers trend over time

BIAKS — Wed, 18 Mar 2026 09:38:23 GMT

Can you try this:

Count( Aggr( IF( Count(Expression1) + Sum({1} 0) > 0 AND RangeSum(Above(Count(Expression1)), 0) = 0, 1 ), MonthYear, Dim1 ) )

You can change Dim1 to Customer, MonthYear to Quarter and Expression1 to Sales.

Re: new customers trend over time

brunobertels — Wed, 18 Mar 2026 12:21:01 GMT

this post may help

https://community.qlik.com/t5/Visualization-and-Usability/New-Customers-for-Selected-Quarter/td-p/2080948

The solution could be :

Prepare Quarter Start Date and lets name it :- vquarterstart in Charts variable:-
then in set expression use the measure:-
Count({<Date={">=$(=vquarterstart)"},CustomerName = e({<Date={"<$(=vquarterstart)"}>})>}CustomerName)

In the variable You can use:-
vquarterstart = addmonths(yearstart(max(Date)),3*(floor((num(month(Max(Date)))-1)/3)))
Or If you have have new version of qlik
you can use
vquarterstart = quarterstart(max(Date))