Use Calculated Values from a Subreport

[RiRo]

Hi Community!

I have a Little strange Problem!

I made a really Hugh an complex monthly Report and now my question is

Is it possible to build a master Report and calculate each supreport for different months and get a computed value from this Report back?

Maybe an example is helpful:
I have a Report, which calculate Servicelevel KPIs per month. Here I get three different Summary Values for a specific month.

So, now our Managers Need is, to have a yearly Report for this SLA KPIs.

Is it possible to make an Overall Report, which run this subreport for each month and can I get this values back tu calculate a yearly SLA KPI?

Thank you very much for your tips and help!

Regards
Rob