Arch registration stats wanted

Does anyone have any data, for either/both the USA and the UK, on the
proportion of practitioners who are-
(a) registered/licensed
(b) members of their prof association (AIA or RIBA)?

Yes, yes, I know I could write to the AIA or NAAB or RIBA or whatever, but
from long experience Brits won't talk to colonials, and Americans keep
trying to send international mail with domestic postage, or have some sort
of phobia about using faxes.
Garry Stevens
Dept of Architectural and Design Science
University of Sydney
NSW 2006
AUSTRALIA
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