The Population Research Center (PRC) is a research and service center within the College of Urban and Public Affairs at Portland State University.  The PRC began in 1956 and was established by the State of Oregon with the responsibility of preparing the Oregon annual certified population estimates for the cities and counties in order to distribute state tax revenues. 

The original program was transferred in 1965 to Portland State University, where it has taken on additional duties, including the Oregon State Data Center, which is the agency in the state responsible for disseminating information from the U.S. Census Bureau.

The population estimates are made as of July 1 of each year and are then certified by December 15. 

The certified population number for the City of Junction City, as of December 15, 2023, is 7,427