The relationship between open access publishing and referencing

"49.9% of papers published in 2019 and 2020 are currently available as OA and 51.3% of references from all papers published during those two years are to papers that are currently available as OA. These two percentages are more similar than the percentage of the papers published between 2010 and 2020 that are OA (i.e., 43.3%), suggesting that the OA percentage of the references of papers is not simply a reflection of the access status of the available papers. When we investigate by OA access type, we observe a similar pattern. The exception is gold OA, with a difference of 9.2 percentage points as opposed to 11.9 percentage points. The results suggest that references in recent papers are more open than one would expect, given OA publication practices in the last decade and that they are more open that the publications in which they appear. This demonstrates that the use of OA exceeds the production of it."