In a letter describing a book he was working on with Irving Geis, Dickerson noted (and illustrated with a
hand-drawn graph) that the number of new structures appeared to be following the exponential law,
n = exp(0.19 y), where n is the number of new structures per year and y is the year number since 1960.
This equation predicted that at the end of 2001, there would be 13,941 crystal structure entries available
in the PDB (approximately 14,000 crystal structures were available in Feb., 2002). Using this equation,
there should be 24,667 crystal structures in 2004.
Thanks to Arthur Arnone, who noticed that there were 57 structures more than Dickerson's equation predicted
in March 2001. Predictions for the rate of NMR structures may be sent to
The RCSB PDB (citation) is managed by two members of the Research Collaboratory for Structural Bioinformatics:
RCSB PDB is a member of the
The RCSB PDB is funded by a grant from the
National Science Foundation, the
National Institutes of Health, and the
US Department of Energy.