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Exhibit B The estimates and projections methodology combines the best current and projected information from the data sources noted above. It is supplemented by the extensive experience of Applied Geographic Solutions in creating accurate and reliable estimates and projections. Summary of Methodology for selected Variables Population The current population of the United States is obtained from the monthly Census Bureau population estimate. This is a very accurate and current estimate of the population and serves as the basis for projection and estimation at lower levels of geographic detail. The five-year projections have been derived from the middle- series projections of the Census Bureau. , The current year estimates rely heavily on the 2000 Census block level population counts, as these provide the most accurate recent data available. These 2000 Census counts replace the 1990 Census counts as the basis for undertaking estimates. In effect, the latest Census tabulation provides a baseline for the estimates and projections. State and county level estimates are based on the compilation of data from a range of Federal and State authorities, including the latest county population estimates from the Census Bureau, the American Community Survey, reviews of building permit statistics, the current population survey (CPS), and additional local sources. Where required, the resulting estimates are then ratio-adjusted so that the sum of the county estimates is equal to the state total, and the state estimates equal to the national total. For the five- and ten-year projections, a similar method is employed. However, rather than using simple straight-line techniques, AGS uses straight-line methods only for growing areas. For declining areas, alog-normal extrapolation is used. This has the effect of slowing decline over time, which is characteristic of long-term population decline at the state level. At the block group level, the population model consists of the application of anon-linear trend model which estimates population given historical patterns, INSOURCE population counts, and the latest Census age distributions (using cohort-survival techniques). Special consideration is given to the population age 65+ by applying ZIP code level counts by age and sex of all Medicare eligible persons. This provides considerable improvement in the estimates of this important segment of the population. The final results are then carefully balanced to the county and city level population estimates to ensure consistency with current Census Bureau estimates. The result is a comprehensive set of population estimates and projections which includes the knowledge of State, County, and private agencies about their detailed areas but also ensures that the total population is consistent with the Census Bureau estimates, which have proved extremely reliable over time. Households and Household Type Total households were modeled by: ^ projecting trends in the population per household over time at the national level to provide a control total; ^ reviewing currently available household size statistics at the State level; and utilizing the current estimates of population by age and sex to determine household formation rates for small areas The ACS data has been extensively used in order to bridge the gap between population estimates and dwelling/postal delivery counts. All household based numbers are initially estimated /projected separately for family and non-family households. Non-family households have been growing in number at a higher rate than family households have over the past several decades. Average household sizes for family households have been decreasing for several decades. However, during the 1990's, the decline has stopped in most areas and has actually reversed in several states. The group quarters population, that is population that is not in households (such as persons in institutions, military barracks, nursing homes, college dormitories, and homeless persons), is expected to Increase slightly during the decade, but remain relatively constant as a percentage of the total population. This is a reflection of two trends: the decreasing armed forces employment since the 1980's and the longer term increasing eldery population which results in high populations in nursing homes and other institutions which cater to the elderly population. As a result, the total group quarters population has been relatively constant.