CAD Productivity

I hope this request does not duplicate any recent discussion on this list.
I just joined today, because I had to find some new sources for a
difficult request which of course is needed asap. The question: Has
anyone done any benchmarking or other productivity type study of CAD in
architectural firms? That is - can it be proven that using CAD is more
efficient than not using it? Any information would be appreciated.
Anelle Kloski, Facilities Design & Construction Lib., Oakland CA.
(akloski@xxxxxxxxxx)
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