Adoption statistics A study published in 2010 showed that roughly 20% of the total output of peer-reviewed articles published in 2008 could be found Openly Accessible.[14] 8.5% of the journal literature could be found free at the publishers’ sites ("Gold OA"), of which 62% in full OA journals, 14% in subscription journals making their electronic versions free after a delay, and 24% as individually open articles (against payment) in otherwise subscription journals. For an additional 11.9% of the articles free full text copies were found elsewhere ("Green OA") in either subject-based repositories (43%), institutional repositories (24%) or on the home pages of the authors or their departments (33%). These copies were further classified into exact copies of the published article (38%), manuscripts as accepted for publishing (46%) or manuscripts as submitted (15%).Of all scientific fields, chemistry had the lowest overall share of OA (13%), while Earth Sciences had the highest (33%). In medicine, biochemistry and chemistry gold publishing in OA journals was more common than the author posting of manuscripts in repositories. In all other fields author-posted green copies dominated the picture. [edit]Journals A study on the development of publishing of Open Access journals from 1993 to 2009 [15] published in 2011 suggests that, measured both by the number of journals as well as by the increases in total article output, direct Gold OA journal publishing has seen rapid growth particularly between the years 2000 and 2009. It was estimated that there were around 19,500 a ticles published OA in 2000, while the number has grown to 191,850 articles in 2009. The journal count for the year 2000 is estimated to have been 740, and 4769 for 2009; numbers which show considerable growth, albeit at a more moderate pace than the article-level growth. These findings support the notion that OA journals have increased both in numbers and in average annual output over time.The development of the number of active OA journals and the number of research articles published in them during the period 1993–2009 is shown in the figure above. If these Gold OA growth curves are extrapolated to the next two decades, the Laakso et al (Bjork) curve would reach 60% in 2019, and the Springer curve would reach 60% in 2025 as shown in the figure below. Gold Open Access growth projections [edit]Self-archiving The Registry of Open Access Repositories (ROAR)[7] indexes the creation, location and growth of open access institutional repositories and their contents. Over 1500 institutional and cross-institutional repositories have been registered in ROAR (see figure below): The Registry of Open Access Mandatory Archiving Policies (ROARMAP [17]) is a searchable international database charting the growth of open-access mandates adopted by universities, research institutions and research funders that require their researchers to provide open access to their peer-reviewed research articles by self-archiving them in an open access repository. To date, mandates have been adopted by over 150 universities and over 50 research funders worldwide (see figure below):