Different levels of measurement depending on how the development and teams are structured:
1) Overall release estimation and planning for the end-customer (no matter if own organization or a client)
2) Onsite perspective
3) Offshore perspective
4) maybe even impact of onsite+offshore on the overall release costs/productivity/time2market/quality/…
Questions to consider:
– Is the releasemanagement done onsite, or is it one big team?
– What are you interested in? Why do you measure functional size? To e.g. ‘control’/’manage’ the offshoring partner? Or to manage the release as a whole for the end-customer? Or to measure productivity for competency/knowledge development? Or to measure productivity or costs for contracting/KPI purposes? etc..
I always evaluate the purposes of measurement, and with outsourcing partners we mostly manage them as part of our own team and we are responsible/accountable. We use FPA for contracting purposes with our clients and to create plannings that involve client-supplier interaction (UAT, deployment, etc), but for internal processes we use FPA for project control to monitor productivity, costs (will be different for onsite and offshore), quality before it goes to the end client, etc and to manage internal sprint backlogs before we do releases to the end client. So in the end there is no big difference between offshore teams or not for us.. but it probably also depends on the scale, type of contracts with your 3rd party suppliers etc.
India is to my knowledge often familiar with Nesma guidelines or they can easily apply them because of already existing IFPUG knowledge.