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From page 313... ... Appendix E Demographic Forecasting and Future Interstate Highway System Demands Guangqing Chi Highways have, since their creation, played an important role in transforming society and affecting population change (Baum-Snow 2007; Vandenbroucke 2008) Read the entire page →
From page 314... ... 314 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM this special report, this appendix focuses on demographic forecasting and future Interstate System demands. In particular, this appendix (1) Read the entire page →
From page 315... ... APPENDIX E 315 change (or economic growth) and highway improvement1 (or travel demand) Read the entire page →
From page 316... ... 316 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM outputs (Eberts 1990) Read the entire page →
From page 317... ... APPENDIX E 317 deficiencies, forecasts of future demand, and environmental impacts. A key indicator of safety and congestion is traffic volume. Read the entire page →
From page 318... ... 318 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM FIGURE E-2 Total population and population density as of 2016 in the United States. Read the entire page →
From page 319... ... APPENDIX E 319 Highway System, which is to connect principal cities and metropolitan areas and to serve the national defense (FHWA 1970) Read the entire page →
From page 320... ... 320 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM POPULATION PROJECTIONS INTO 2060 AT THE COUNTY LEVEL Projection Methodology, Procedure, and Assumptions Cohort Component Methods There are many methods for population forecasting, including extrapolation projections and time series models, postcensal population estimation models, knowledge-based regression models and structural models, conditional probabilistic models, integrated land use models, population forecasting by grid cells, and cohort component methods (Chi 2009; Smith et al. 2013; Wilson and Rees 2005) Read the entire page →
From page 321... ... APPENDIX E 321 of net migration across space could cancel out each other at coarser (or aggregated) levels. Read the entire page →
From page 322... ... 322 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM P2011 = P2010 + B2010,2011 – D2010,2011 + M2010,2011 P2017 = P2016 + B2016,2017 – D2016,2017 + M2016,2017 P2060 = P2059 + B2059,2060 – D2059,2060 + M2059,2060 Population estimates and projections are developed for each individual county. This is done for each age (0–84 and 85+ years) Read the entire page →
From page 323... ... APPENDIX E 323 Projecting Births A new birth cohort is formed each year to be added to the population. For example, the cohort that is born between July 1, 2016, and June 30, 2017, is added to the population in 2017. Read the entire page →
From page 324... ... 324 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM In practice, population projections are often adjusted to improve forecasting accuracy. Adjusting population projections can involve many steps. Read the entire page →
From page 325... ... APPENDIX E 325 FIGURE E-4 Population in 2010 and projected populations in 2020, 2030, 2040, 2050, and 2060. continued Read the entire page →
From page 326... ... 326 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM FIGURE E-4 Continued Read the entire page →
From page 327... ... APPENDIX E 327 FIGURE E-5 Population density in 2010 and projected population densities in 2020, 2030, 2040, 2050, and 2060. continued Read the entire page →
From page 328... ... 328 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM FIGURE E-5 Continued Read the entire page →
From page 329... ... APPENDIX E 329 FIGURE E-6 Population change, percentage population change, and population density change, 2010–2060. Read the entire page →
From page 330... ... 330 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM There seem to be more counties that will experience population decline. This includes many counties from the northeast corner to the Appalachian region, counties bordering the Great Lakes except Lake Michigan, counties along the Mississippi River, the Deep South states, and Alaska. Read the entire page →
From page 331... ... APPENDIX E 331 FIGURE E-7 Projected population and population density in 2060 and the Interstate Highway System. TABLE E-2 Descriptive Statistics of Population and Proximity to the Interstate System in 2060 N Mean SD Min. Read the entire page →
From page 332... ... 332 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM FIGURE E-8 Population change, percentage population change, and population density change, 2010–2060, and the Interstate Highway System. Read the entire page →
From page 333... ... APPENDIX E 333 The overall population change from 2010 to 2060 in the United States is 38.56 percent for counties with Interstates and 14.23 percent for counties without Interstates. Counties Along or Close to the Interstate Highway System That May Need Additional or Less Capacity The counties that are projected to gain or lose population along the Interstate Highway System are highlighted in Figure E-9. Read the entire page →
From page 334... ... 334 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Counties that fall beyond 20 miles of the Interstate System are projected to gain an average of only 1,060 people; on average these counties are projected to lose 7.45 percent population. Note that the mean percentage change is calculated as the average percentage change in each county. Read the entire page →
From page 335... ... APPENDIX E 335 TABLE E-4 Population Change from 2010 to 2060 and Proximity to the Interstate Highway System N Mean SD Min. Read the entire page →
From page 336... ... 336 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM on the with-or-without -- Interstate network results, but the former includes more surrounding counties. Counties Without Interstate Highways But Projected to Experience Rapid Population Growth and Population Density Increase The counties identified in the previous section either have the Interstate highways or are within 20 miles of the system. Read the entire page →
From page 337... ... APPENDIX E 337 IMPLICATIONS OF AGING POPULATION, MILLENNIALS, IMMIGRANTS, AND TELECOMMUTING Population Pyramids and Age Variations of Interstate System Users Demographic characteristics can play a role in travel patterns and the demand for different travel modes. In the United States the number of vehicle-miles traveled (VMT) Read the entire page →
From page 338... ... 338 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Population pyramids from 2010 to 2060 are illustrated in Figure E-14. Although all age groups are projected to increase over the 50 years, the elderly (age 65 and older) Read the entire page →
From page 339... ... APPENDIX E 339 FIGURE E-14 Population pyramids in 2010, 2020, 2030, 2040, 2050, and 2060. make fewer trips, they often couple multiple destinations within one trip (going to the store, visiting a relative, running an errand, and then returning home) Read the entire page →
From page 340... ... 340 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM trips, and they drive more miles on these trips than younger people (Collia et al. Read the entire page →
From page 341... ... APPENDIX E 341 The Young Population and the Millennials Interestingly, fewer young people are obtaining their driver's licenses than in previous generations. Although 77 percent of 18-year-olds in 1990 had a driver's license, a study in 2013 found that only 54 percent of 18-yearolds did (Research Triangle Institute 1991; Tefft et al. Read the entire page →
From page 342... ... 342 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM 2014) , are a popular subset of the population for study. Read the entire page →
From page 343... ... APPENDIX E 343 FIGURE E-19 Distribution of the young population in 2015 at the county level. FIGURE E-20 Projected young population (ages 15–34) Read the entire page →
From page 344... ... 344 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM percentage of the population comprising those born outside the country is projected to increase from 13 to 19 percent. Among the foreign-born population, Hispanics make up the largest racial/ethnic category. Read the entire page →
From page 345... ... APPENDIX E 345 telecommuting technology, the impact has been mixed (Zmud et al. Read the entire page →
From page 346... ... 346 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM CONCLUSIONS Population growth demands higher Interstate System capacity. To upgrade and restore the Interstate Highway System as a premier system for the 21st century, demographic forecasting is a must before any transportation planning and decision activities. Read the entire page →
From page 347... ... APPENDIX E 347 Interstate highway are included in the analysis. The areas that may need additional Interstate capacity, based on their population projections, are particularly strong in counties along I-5 from Washington to San Diego, California; counties from Los Angeles, California, to Phoenix, Arizona, along I-10; counties from Los Angeles to Albuquerque, New Mexico, along I-40; counties from Los Angeles to Utah along I-15; counties along I-20, I-35, and I-45 spreading from Dallas, Texas; counties along I-20 from San Antonio, Texas, to Pensacola, Florida; the lower Florida counties; counties in the big triangle of Atlanta, Georgia, the Triangle of North Carolina, and Nashville, Tennessee; counties along I-95 from Washington, D.C., to Boston, Massachusetts; and counties from Minneapolis, Minnesota, to Detroit, Michigan, along I-90 and I-94. Read the entire page →
From page 348... ... 348 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM REFERENCES Abbreviations DOT Department of Transportation FHWA Federal Highway Administration U.S. Read the entire page →
From page 349... ... APPENDIX E 349 Lichter, D Read the entire page →
From page 350... ... 350 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Thiel, F Read the entire page →

From page 313...

... Appendix E Demographic Forecasting and Future Interstate Highway System Demands Guangqing Chi Highways have, since their creation, played an important role in transforming society and affecting population change (Baum-Snow 2007; Vandenbroucke 2008)