How do I count the number of clients that have multiple service within 60 days of a specific service?

[mjirges]

I am trying to count the number of clients that have more then 1 service after a particular service (Comprehensive Assessment).

In order to be counted, more then 1 service must be present within 60 days of the Comprehensive.

All relevant data is in the same table/fields. The "Comprehensive" Service and subsequent services are all in the same place (example in screenshot). 

In the example, Clients 1, 2 and 5 would be counted. 

1 has four services that count

2 has three services that count

3 does not have a Comprehensive, therefore wouldn't count

4 only has one service that counts, therefore wouldn't be included

5 has two services after the Comprehensive, therefore would count

6 doesn't have any services in the timeframe, therefore wouldn't count.

What kind of expression would I use? I don't have access to the script, so I can only write this in an expression. 

[pravinboniface]

Not the most elegant solution, but if you can sort the table by client_id, Service_Name and Service_Date, then you can use something like this.

if(below(TOTAL client_id)=client_id and
   Service_Name='Comprehensive' and
   interval(below(TOTAL Service_Date)- Service_Date,'d') < 60 and
   interval(below(TOTAL Service_Date)- Service_Date,'d') >=0, 1,0)