The publication, "The End Is Near, A Comprehensive Compilation Of Watchtower Dates" by Freeminds, shows many quotes from WTS rags referring to the dates RR is referring to.
1914: "We see no reason for changing the figures- nor could we change them if we would. They are, we believe, God's dates, not ours. But bear in mind that the end of 1914 is not the date for the beginning, but for the end of the time of trouble."(WT Jul 15 1894 266 repr 1677
1915: "In view of this strong bible evidence concerning the Times of the Gentiles, we consider it an established truth that the final end of the kingdoms of this world, and the full establishment of the kingdom of God, will be accomplished near the end of A.D. 1915, (TIAH 1915 ed 99)
1918: "The parallel, therefor, would establish definately that the harvest would close forty years thereafter, to wit, in the spring of A.D. 1918. If this is true, and the evidence is very conclusive that it is true, the we have only a few months in which to labor before the great night settles down when no man can work." (WR Oct 1 1917 6149)
1925: [By 1925] You will have secured the services of the best decorators you can find. Some of them used to be undertakers; but since there are no more people dying, they have had to seek some new occupation. Their experience as undertakers prepared them to become decorators with very little difficulty." (TWTP 228)
1945: ?
1975:...acknowledged the Society's responsibilty for some of the disappointment a number felt regarding 1975."(YEAR 1980 30-1)
1984:"Some of that 'generation[of 1914] could survive until the end of the century. But there are many indications that 'the end' is much closer than that!"(WT Mar 1 1984 18-9)
1994: "Bible prophecies indicate that Satan's world has been in it's last days for nearly 80 years now, since the pivotal year 1914. This world is nearing it's end."(WT Mar 15 1994 20)
1999: "The apostle Paul was spearheading the Christian missionary activity. He was also laying a foundation for a work that would be completed in our 20th century."(WT Jan 1 1989 12) [bound volumn changed "20th century" to "day"]
TR