First Census | Cle Elum, WA
The first Cle Elum census of record was in the year 1900 and gave Cle Elum a population of 250. By 1905, there were over 1,500 people in the town, and 2,749 by 1910.
(Cle Elum -- Thumbnail History, HistoryLink.org Essay 10646). (SWIFTWATER, History of Cle Elum 1848-1955, published by Northern Kittitas County Historical Society, 2014, Page 17 and 36)