Portra film ISO rating?

[DLee]

I just got some 400NP back from the lab and it's pretty thin. After I had taken the film to the lab I read (in the forum here) that 4X5 Portra 400 should be opened a stop and rated at 200. I'm guessing this applies to 120 sized film as well? What about Portra 160? Should I shoot that down at 80 ISO?

Or are my shutter speeds kinda messed up?

Thanks, Dennis

Amendment: I forgot that my film is super old, that's probably the problem here.