3 September 2019 — 1454 mdt
Cascade County’s share of Montana’s population
has declined by one-third since 1970
And Silver Bow’s share has declined by almost one-half. Another Democratic stronghold, Deer Lodge county, not displayed on the plot below, declined from a share of 2.25 percent in 1970 to 0.86 percent in 2018. During the same period, Yellowstone, Lewis and Clark, Missoula, Ravalli, Flathead, and Gallatin Counties increased their share of Montana’s population (download Excel spreadsheet of all Montana counties).
In 1970, the nine counties plotted on the graph comprised 58 percent of Montana’s population. In 2018, their share had increased to 71 percent. Montana’s population is concentrating in its largest counties, and more generally in the state’s western counties.
