Arbitron Metro population estimates are based on U.S. Census information and updated annually, using a variety of local, state and federal data.
Metro population estimates are released each year for the Fall survey and are projected to January 1 of the next year. The estimates are created and copyrighted by Claritas, Inc.
There are three factors that can cause a difference between Arbitron’s estimates for Metro populations and population estimates from other sources.
Arbitron ratings are created using a seven-day personal listening diary filled out by persons 12 years of age or older. As a result, our market ranks are based on the population of persons 12 years and older (“persons 12+”) only. Most other organizations, however, use population estimates for total population (“persons 0+”).
An example of how this can impact the population estimates is the Albany, GA, radio Metro. According to Census 2000 data, the Metro had a population of 120,822 persons 0+ and 98,228 persons 12+.
There may be differences between the ways different sources define the geography of a Metro. This is usually a difference in which counties are included in the Metro and which are not. In the case of Albany, GA, Arbitron’s radio Metro is made up of two Georgia counties: Dougherty and Lee. The Federal government’s Metropolitan Statistical Area (MSA) includes three additional counties: Baker, Terrell and Worth, GA. For Census 2000, the MSA had 167,079 persons 12+ while the radio Metro had 98,228.
There may be differences between Metro estimates when they utilize data from different sources. The difference can be a result of a number of issues, including when the estimates were developed, what data preparation methods were employed and what inputs and methods were used.