This project is funded by the State of Oregon through the Department of Land Conservation and Development (DLCD).
Oregon -- Population -- Statistics, Demographic surveys -- Oregon, Population forecasting -- Oregon -- Yamhill County
Different areas within Oregon counties experience different growth patterns. Those patterns combine to collectively determine county‐level demographic changes. Yamhill County is comprised of two types of areas: its urban‐growth boundary (UGB) areas (Amity, Carlton, Dayton, Dundee, the portions of Gaston within Yamhill County, Lafayette, McMinnville, Newberg, Sheridan, the portions of Willamina within Yamhill County, and the City of Yamhill) and the area outside of those UGBs.
Yamhill County’s total population increased during the 2000s, growing at an average of 1.6 percent annually (see Figure 1). Small sub‐areas in northeastern Yamhill County—such as Carlton, Gaston, Lafayette, and Yamhill—experienced faster population growth than the county, averaging between 2.5 and 4 percent growth annually. Large sub‐areas—McMinnville and Newberg—grew faster than the county, too, at about 2 percent annually. In contrast, areas in southern Yamhill—Amity, Sheridan, and Willamina—grew the slowest, around or below 1 percent annually.
The population growth that occurred in Yamhill County between 2000 and 2010 resulted mostly from strong net in‐migration of adults older than 30, some with children. Population growth due to natural increase (births minus deaths) was positive during the same time period but represented a smaller proportion of growth. After 2007, Yamhill County’s natural increase began to dip but remained positive through 2018. This was due to several factors. Most notably, between 2000 and 2010, Yamhill County’s total fertility rate fell over 50 percent faster than the statewide rate. The effects of this trend were compounded by net out‐migration of adults in their late twenties and early thirties, a migration pattern common in areas without a major city. These factors—combined with nationwide population aging—led to fewer births and more deaths each year and, thus, declining natural increase.
Portland State University. Population Research Center; Chun, Nicholas; Rancik, Kevin; Runge, Paul; Cunningham, Mac; Loftus, Deborah; and Rynerson, Charles, "Coordinated Population Forecast for Yamhill County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2020-2070" (2020). Oregon Population Forecast Program. 64.