I agree that it is best to budget what is actually needed and can be
justified in the "supply" category, but the specific amount depends
greatly on the nature of the project.  For general trends, you might
look at the peer review released on 02/08/00 by the Office of
Extramural Affairs for modular grants.  The pdf file includes
interesting graphs of general trends by institutes.   It is hard to
read percentages carefully, but supplies seems to range from about
18-20% to about 25-30% of competing R01 awards for 97 &
98.  Percentages for equipment are actually less.  I assume the
labels are not inadvertently reversed on the chart.  Also, the
frequency distribution for first year direct cost requests were
greatest (in nearly equal numbers) at $175 & $200K.

Source:
http://grants.nih.gov/grants/funding/modular/modular.htm?

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Terry A. May, Ph.D.
 Director of Research Development
 524 S. Kedzie
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 xxxxxx@pilot.msu.edu
 517/432-7140 Office/voice mail  (LSC Main Number 353-1768)
 432-9555 Fax
 http://www.msu.edu/unit/vprgs/LSC/LSC%20Page.htm
 http://www.msu.edu/~biomed/
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