The Dramatic Growth of Open Access continues, on both the gold (open access publishing) and green (open access self-archiving) roads. Some noteworthy highlights: PubMedCentral, the world's largest open access archive, noted a significant milestone on June 21: the millionth article (thanks to Peter Suber on Open Access News. An OAIster search now includes close to 12 million items, an increase of over 4 million items over the past year. The number of repositories continues to increase; OAIster searches include more than 200 more repositories than one year ago. Scientific Commons now includes more than 12 million items, by more than 6 million authors.
The Directory of Open Access Journals lists 2,731 titles, an increase of 439 titles from June 2006, or an average of 1.2 new titles per calendar day. According to Jan Sczepanski on Liblicense at http://www.library.yale.edu/~llicense/ListArchives/0706/msg00135.html, there were over 13,000 open access journals listed on Elektronische Zeitschriftenbibliotek - Electronic Journals Library.
Growth rates of open access archives tracked range from 14% over the past year (arXiv), 33% for rePEC, and 54% for E-LIS and the Canadian Association of Research Libraries (CARL) Metadata Harvester.
For full data and additional comments, please see The Dramatic Growth of Open Access: Open Data Edition, June 30, 2007.
This post is part of the Dramatic Growth of Open Access Series.
Postscript added July 15: 1,000 Journals using Open Journal Systems (OJS)