The CWTS Leiden Ranking is compiled in four-year intervals. Although the name would suggest otherwise, it is rather a database that collects and publishes information on publications and citations. The calculation of OA publications is performed by Unpaywall. Starting with the Web of Science directory, they scour OA versions of articles using their DOI identifiers.
– It is positive that Stockholm University has the top position in Sweden, but it is only 60-percent, which is good progress towards the target of 100-percent by 2020, says Library Director Wilhelm Widmark.
The ranking is valid for the years 2014-2017, thus not including publications from 2018-2019 – years that have entailed several major positive changes for Open Access at Stockholm University.
– Since we signed several transformative agreements, and agreements with pure Open Access publishers, the figures ought to increase considerably in the future, says Wilhelm Widmark.