X series ISO Inflation

Engineers: This set of measurements gives an ISO value of 145±3. I think we should call it "150"

Team leader: Nah, not enough room in the software to store that many ISO values. Let's round down and call it "100".

Marketing team: The engineers suggest 150? That's about, about, hm, I dunno. Anyway, I don't like how the "5" comes out in the typeset we use in our brochures. I know! Let's just round it up. That would be 200. Let's call it "200". Sounds good, what's for lunch?