CrossRef Indicators
The latest stats on CrossRef activity have been posted at
http://www.crossref.org/01company/crossref_indicators.html
CROSSREF INDICATORS (September 01, 2006)
Total no. participating publishers & societies 1,671
% of non-profit publishers 64%
Total no. participating libraries 1,083
No. journals covered 15,121
No. DOIs registered to date 22,320,497
No. DOIs deposited in previous month 294,257
No. DOIs retrieved (matched references) in previous month 4,503,094
DOI resolutions (end-user clicks) in previous month n/a