Table 2.
Proportion of publisher-provided (gold) open access in major indexes
| Articles indexed in Scopus | 2008 | 2009 | 2010 | 2011 |
|---|---|---|---|---|
| Totala | 1,469,286 | 1,550,413 | 1,588,636 | 1,658,643 |
| In full immediate OA journalsb | 118,751 | 133,817 | 163,670 | 181,706 |
| Share of articles published in full immediate OA journals | 8.1% | 8.6% | 10.3% | 11% |
| Hybrid OAc | 4,718 | 8,095 | 10,135 | 12,089 |
| Delayed OAd | 78,054 | 82,271 | 81,404 | 85,714 |
| Total share OA | 13.7% | 14.5% | 16.1% | 16.9% |
| Articles indexed in Web of Knowledge | 2008 | 2009 | 2010 | 2011 |
| Totale | 1,154,803 | 1,203,692 | 1,235,202 | 1,294,051 |
| In full immediate OA journalsb | 76,537 | 85,852 | 103,514 | 116,192 |
| Share of articles published in full immediate OA journals | 6.6% | 7.1% | 8.4% | 9.0% |
| Hybrid OAc | 3774 | 6476 | 8108 | 9671 |
| Delayed OAd | 76,076 | 80,338 | 79,058 | 83,420 |
| Total share OA | 13.5% | 14.3% | 15.4% | 16.2% |
aAll articles + reviews, retrieved 22 May 2012 through scopus.com; bresults of this study; cresults of previous research [8]; dresults of an ongoing study by the authors, based on absolute volume calculations for articles in 462 unique journals available through HighWire Press, PubMed Central, Elsevier and so on with an open access delay of 12 months or less; eall articles + reviews included in the Science Citation Index Expanded, Social Sciences Citation Index, Arts & Humanities Citation Index, retrieved 22 May 2012 through apps.webofknowledge.com. OA: open access.