Tower Bible and Tract Society, of which Judge Rutherford is the president and general manager." "Zone servants" (now known as circuit overseers) were appointed to supervise congregations. In a Watchtower article Rutherford declared the need for congregations to "get in line" with the changed structure. By 1942, the year of his death, worldwide attendance at the annual Memorial of Christ's death was 140,450 though his restructuring of the Bible Student community coincided with a dramatic loss of followers during the 1920s and 1930s. Worldwide attendance of the annual Memorial of Christ's death fell from 90,434 in 1925 to 17,380 in 1928. Memorial attendance figures did not surpass 90,000 again until 1940. Author Tony Wills, who analyzed attendance and "field worker" statistics, suggests it was the "more dedicated" Bible Students who quit through the 1920s, to be replaced by newcomers in larger numbers, although Rutherford dismissed the loss of the original Bible Students as the Lord "shaking out" the unfaithful. In the 1942 Yearbook of Jehovah's Witnesses, Rutherford wrote that the year's achievements "would, on the face of it, show that the Theocratic witness work on earth is about done". Doctrinal changes In July 1917, Rutherford had The Finished Mystery published as a seventh volume of the Studies in the Scriptures series. The volume, though written by Fisher and Woodworth, was advertised as Russell's "posthumous work" and "last legacy" but contained several interpretations and viewpoints not espoused by Russell, including an urging of all Bible Students to cast judgment upon Christendom and its clergy, the adoption of new dates for the fulfillment of particular prophecies, a claim that salvation is tied to membership within the Watch Tower Society, as well as shunning and censuring any who reject the interpretations given in the volume or related articles in Zion's Watch Tower magazine. In the February 1918 discourse "Millions Now Living Will Never Die" (printed in booklet form in May 1920) a revision of Russell's calculation of a "Jubilee type" was presented, changing it from 1875 to 1925, despite Russell's rejection of such a change a few months prior to his death. In October 1920 the Society published a new edition of Russell's 1881 Tabernacle Shadows of the Better Sacrifices. It included an appendix introducing many alterations or reinterpretations of Russell's original views on the death of Jesus and the role of Christ's followers in heaven as typified in the ceremonies of the