title: Chemical Abstracts Service Chemical Registry System. 11. Substance-related statistics: update and additions.
abstract: Statistics are updated for types of substances, ring systems, and elemental composition that have been determined for the Chemical Abstracts Service Registry Structure File at different points in time. This paper reports the updated figures and in addition some new statistics and offers some comparisons to show various shifts in file characteristics.
authors.affiliation: Chemical Abstracts Service, Columbus, Ohio 43210.
authors.forename: R E
authors.initials: RE
authors.lastname: Stobaugh
mesh_terms: D000043:Abstracting and Indexing; D055598:Chemical Phenomena; D002621:Chemistry; D003199:Computer Systems; D015394:Molecular Structure; D012042:Registries; D013223:Statistics as Topic; D013997:Time Factors