Yearly trends in PubMed (Medline) indexing by
language
percentage of entries
The scale on the right is for the percentage of papers published yearly in english and indexed by Medline (having "eng" in the "LA" field, the full black line) from all papers in that year; the scale on the left is for the percentage of papers published in any other language.
In the last 50 years
In the last 20 years