Hi Syd,
My recollection was that we used the 70% of the USA rate when in the USA and not externally because the rate often was misjudged outside... but it may be that I was entirely reversed on that recollection. Maybe it was the reverse. I honestly am not sure and haven't found any documentation on it. I've submitted mine already but happy to use whatever Hugh says is right. ;-)
Many thanks,
James
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Dr James Cummings, James.Cummings@newcastle.ac.uk
School of English Literature, Language, and Linguistics, Newcastle University