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In our case study, population change in terms of population counts as reported by the U.S. Census Bureau is the response variable (or dependent variable) and is expressed as the natural log of population in a census year over the population ten years earlier. For example, the measure of the growth rate from 2000 to 2010 is the natural log of the 2010 population divided by the 2000 population. This measure of population change helps achieve a normal “bell-shaped” distribution; makes interpreting the population change rate easier (growth is shown by a positive value, decline is shown by a negative value, and no change at all is shown by zero); and accounts for initial population size (Chi, 2009). The population data for this case study are provided by decennial U.S. Census Bureau censuses from 1970 to 2010.

Figure 1.4 shows population change in Wisconsin in four time periods: 1970–1980, 1980–1990, 1990–2000, and 2000–2010. From 1970 to 1980, relatively high population growth occurred in rural and suburban areas. The 1970s marked a rural renaissance for the first time in Wisconsin, also called “turnaround migration” by rural demographers, as natural amenities and employment opportunities attracted migrants to the amenity-rich rural areas (Johnson, 1999). During this time, rural and suburban MCDs experienced higher population growth rates than urban MCDs: the average population growth rate was 13.4 percent for rural MCDs, 16.5 percent for suburban MCDs, and 11.7 percent for urban MCDs (Table 1.1).

Description

Figure 1.4 ⬢ Population change at the MCD level in 1970–1980, 1980–1990, 1990–2000, and 2000–2010 in Wisconsin

Table 1.1

Note: The numbers in each cell represent the average population change rate at the MCD level. Standard deviations are in parentheses.

From 1980 to 1990, a majority of MCDs experienced population decline; it was the slowest growth decade in the history of Wisconsin. The population redistribution pattern was renewed metropolitan growth, mainly due to economic disruptions such as the farm debt crisis, deindustrialization (which downsized the manufacturing), and urban revival (which stopped people migrating to rural areas). In this decade, the average population growth rate in urban MCDs (6.3 percent) was much higher than that in suburban MCDs (3.8 percent), which was much higher than that in rural MCDs (0.1 percent).

From 1990 to 2000, rural areas rebounded as an improved economy and the areas’ natural amenities attracted retirees. Relatively high population growth occurred in northern Wisconsin, central Wisconsin, and some suburban areas. The population growth rate of rural MCDs (9.1 percent) was similar to that of urban MCDs (10.6 percent), and the average population growth rate in suburban MCDs (13.1 percent) was relatively higher than those in rural and urban MCDs.

From 2000 to 2010, the population redistribution pattern was selective deconcentration; technological innovations in communications and transportation, companioned with the economic crisis that occurred in 2008, made migration more selective. It appears that population growth occurred mostly in suburban areas. The average population growth rate of MCDs from 2000 to 2010 in Wisconsin was 3.6 percent. The growth rate varies spatially along the urban-rural continuum: the average population growth rate was 1.8 percent in rural MCDs, 9 percent in suburban MCDs, and 6.1 percent in urban MCDs.