There is a very interesting thread in the BioNLP list, about indexing statistics and growth of Medline. As the archive of the list is public, I post here the most interesting links in the thread on my opinion.
- Medline Detailed Indexing Statistics (1965-2007): It covers journals and citations.
- Medline Data Entry by Fiscal Year (1995-2007): It covers the way citations were entered (typed, OCRed, XML).
- Key Medline Indicators (2004-2008): Most exhaustive, with citations, journals, searches, and more. With links to previous periods.
Kevin Cohen has also cited an interesting paper that analyzes the growth of PubMed:
L. Hunter, K. Cohen, 2006. Biomedical Language Processing: Perspective What's Beyond PubMed? Molecular Cell 21, 589-594, March 3.
Hey, what about information overload? Pretty exponential.