Customer Retention with dynamic range

[sulistio]

Hi, I need help for my problem below

I have sales data, examples

And i have tables customer service

My goal is to calculate about customer retention.

the rules is for retention free service 1 month  in Feb19 :

Count of police No service in Feb, devide by count of sales 1 month ago (Jan)

: 1/2 = 50%

the rules is for retention free service 2 month  in Mar19 :

Count of police No service in Mar, devide by count of sales 2month ago (Jan)

: 2/2 = 100%

Table for sales and customer service is different.

and how to set the expression to get 50% and 100%

Thank You

[sunny_talwar]

I am not sure I understand the example here... How are you getting to these numbers based on the sample provided?

[sulistio]

Ya, i got from the sample.

We calculate free service 1 month in feb 19 calculate: count of vehicle that doing free service 1 month in feb19 divided by count of sales 1 month ago = 1/2 = 50%

same if we want calculate retention free service 2 month in feb 19, we calculate count of vehicle doing free service 2 in feb19 devided by count sales 2 month ago: 2/2 = 100%