Within a Wilhemsdorf, Germany, edition of a Selichot volume, I found three separate handwritten sheets of paper. Each contains the list of piyutim chosen by the congregation to be recited that year on Yom Kippur for each of the prayers.
Over the generations, German Jewry had accumulated numerous different Selichot prayers, and the custom developed to rotate the selections for each year, thus ensuring that none would be forgotten and that all shall be said at least occasionally.
The three sheets were for the year 5736 (1935), 5737 (1936) and 5739 (1938). Some communities had these lists printed every year to be distributed to the congregants, and occasionally such ephemera were preserved within the prayerbooks of the era.