Update July 6: please note corrections. Growth for this quarter and this year are higher than originally reported!
Highlights: the growth of open access continues to amaze! The Directory of Open Access Journals added 750 new titles over the past year, a rate of increase of 2 titles per calendar day. This is close to double the growth rate of 1.2 titles per calendar day as reported in June 2007. OAIster recently passed a significant milestone, the 1,000th repository harvested. OAIster added close to 5 million items over the past year, for a growth rate of 30%. A Scientific Commons search now encompasses close to 20 million items.
PubMedCentral is showing early signs of success of the new NIH mandate policy. 466 journals now participate voluntarily in PMC (up from 410 in March); of these, 355 or 75% provide immediate free access. There is a marked increase in the percentage of NIH-funded items that are freely available shortly after publication (30, 60, or 90 days after publication). For example, the percentage of NIH-funded articles freely available within 30 days of publication has increased 50%, from 6 to 9%. (Thanks to Jim Till for the earlier data and search strategy). This remarkable increase in free access immediately or soon after publication is important because it exceeds expectations. NIH allows up to 12-month embargo, but clearly not everyone is interested in taking advantage of this generosity.
RePEC and E-LIS have had strong growth over the past year, each increasing by about 25%. The only negative is Highwire Free, which grew slightly overall but lost one fully free site, producing a small but rare negative growth number. Björk Roosr, and Lauri presented an important study at the ELPUB conference, reporting that close to 20% of the world's peer-reviewed literature published in 2006 is freely available, whether published as open access or self-archived by the author.
The Open Data Edition of Dramatic Growth can be found here. A plain data version (without quarterly growth) is available here - note the second sheet which has data on PMC titles. A list of journals participating in PMC and analysis by time of free access is available here. If anyone would like to collaborate on these documents (even just to be able to download them), please let me know. Update July 2nd: excel versions are now available to download from the Dataverse Network.
Directory of Open Access Journals
DOAJ added 179 titles this quarter, a slight decrease from the first quarter, or 750 over the past year, a growth rate of 22%. DOAJ is adding new titles at the rate of 2 titles per calendar day, up from the average of 1.4 reported for last year. The number of DOAJ journals providing searching at the article level has increased, as has the number of articles which can be searched through DOAJ.
OAIster now includes 16.9 million records, added more than 1.3 million records this quarter, close to 5 million over the past year, for a very strong growth rate of close to 30 %. the 1,000 repository on June 28, 2008
Scientific Commons now includes over 19.5 million items, and added more than 1.4 million records and over half a million authors this quarter, for a strong growth rate of more than 20% over the past year.
ELPUB article Björk, Bo-Christer; Roosr, Annikki; Lauri, Mari (2008) Global annual volume of peer reviewed scholarly articles and the share available via different open access options, ELPUB2008. Openness in Digital Publishing: Awareness, Discovery and Access - Proceedings of the 12th International Conference on Electronic Publishing held in Toronto, Canada 25-27 June 2008 / Edited by: Leslie Chan and Susanne Mornatti. ISBN 978-0-7727-6315-0, 2008, pp. 178-186 ELPUB 2008
Jim Till. More baseline data from pubmed. Be Openly Accessible or Be Obscure.
This post is part of the Dramatic Growth of Open Access Series.