I wonder if I could answer that in a in a different way because clearly rather there's the option, rather than reduction the operational capability which was really the er  initiative that  had begun in nineteen ninety two, there is the option of course of er adjusting the total numbers and that would er have an overall bearing on the total programme cost but cert because certainly the judgement of the er  the chiefs of staff was that er as far as the U K was concerned then we we should retain the operational capability as I explained earlier an n and not decrease it in any significant extent because if we did that then we could end up er with an inferior capability against a potential threat.