CrossRef Indicators
The latest stats on CrossRef activity have been posted at
http://www.crossref.org/01company/crossref_indicators.html
CROSSREF INDICATORS (December 08, 2006)
Total no. participating publishers & societies 2,287
% of non-profit publishers 68%
Total no. participating libraries 1,146
No. journals covered 15,453
No. DOIs registered to date 23,979,913
No. DOIs deposited in previous month 505,729
No. DOIs retrieved (matched references) in previous month 5,623,684
DOI resolutions (end-user clicks) in previous month n/a