History of the Encyclopædia Britannica the criteria by which the articles were sorted were not obvious even to scholars, despite Dr. Adler's claims that the sorting followed naturally from the "Propædia's" outline of all knowledge. In 1985, the "Britannica" responded to reader requests by restoring the index as a two-volume set. The number of topics indexed by the "Britannica" has fluctuated from 500,000 (1985, the same as in 1954) to 400,000 (1989,1991) to 700,000 in the current 2007 print version. Presumably, this recent increase reflects the introduction of efficient electronic indexing, since the size of the encyclopedia has remained nearly constant at approximately 40 million
Encyclopædia Britannica analysed systematically by its former editor Walter Yust. Eventually, the Britannica turned to focus more on its online edition. The has been compared with other print encyclopaedias, both qualitatively and quantitatively. A well-known comparison is that of Kenneth Kister, who gave a qualitative and quantitative comparison of the "Britannica" with two comparable encyclopaedias, "Collier's Encyclopedia" and the "Encyclopedia Americana". For the quantitative analysis, ten articles were selected at random—circumcision, Charles Drew, Galileo, Philip Glass, heart disease, IQ, panda bear, sexual harassment, Shroud of Turin and Uzbekistan—and letter grades of A–D or F were awarded in four categories: coverage, accuracy, clarity,