Yearly trends in PubMed (Medline) indexing by
country of publication
percentage of entries in a given year
The scale on the right is for percentage of papers published yearly in journals havin the Medline 'PL' (place of publication) as 'United States' or 'England'; the scale on the left is for the percentage of papers published in journals located in other countries. "sco" means Scotland.
Some journals do not have a 'PL' field.
