How many research papers are freely available?

Beneath this ferment, the proportion of research papers freely available is slowly and steadily creeping upwards. The chart shows the proportion of papers indexed on the (largely biomedical) PubMed repository each year that are now freely accessible: in 2009, it’s above 28%. (Some of this literature is not immediately available at the time that it is published, because of journal policies that impose embargo periods on when material can become free). Those numbers are even more impressive than a study last year which found that around 20% of research papers published in 2008 were freely available on the internet.

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