Population Dynamics of the Great Plains: 1950 to 2007
http://www.census.gov/prod/2009pubs/p25-1137.pdf
Describes the demographic trends for an area that constitutes 18% of the U.S. landmass but only 3% of the population. Although the Great Plains population more than doubled over the measured time period, 244 of the 376 counties in the region saw their populations decline. From the Census Bureau.
