University of Missouri Extension  |  Division of Applied Social Sciences  |  College of Agriculture, Food and Natural Resources

State Overview -- Changes in the Age Distribution of Missouri Population, 1990-2000

As reported by the 2000 Population Census Missouri’s population increased from 5,117,073 in 1990 to 5,595,211 in 2000 - a 9.3 percent increase - far above the 4.1 percent increase from 1980 to 1990. In addition to population change, the Census reports much additional information about characteristics of the population, such as age, race, gender, household composition, income, employment, etc. The age distribution of Missouri’s population by county and region is the focus of this section of the Regional Profiles. Age is one of the more important and useful characteristics of the population because of its effect on school and higher education enrollment, demand for housing, health care, public services, consumer products and services, size of the labor force, etc.

Implications of Change in the Population of Major Age Groups

The Census reports of age of the population are usually reported as the number of persons in various age groups beginning with children under age 5, followed by children age 5-9, age 10-14, teenagers age 15-17, young adults age 18-19 and age 20-24. Adult age groups are reported by ten-year intervals beginning with age 25-34 and continuing up through age 85 and over - a total of 13 age groups. However, for purposes of this report and analysis, we have combined several of the age categories into the 8 different age groups as shown in Graph 1. The purpose for combining the age of the population into the larger age groups is to facilitate analysis and reporting of implications of changes in the age distribution of the population for public policy, provision of services, etc.

Graph 1
Percent Change in Missouri Population by Selected Age Cohorts, 1990-2000

Specifically the following age groups from Graph 1 are regarded as having especially important social and economic implications:

  • Seniors: for the past generation or more, it has become common place to refer to persons age 65 and over as seniors. Having reached age 65 makes them eligible for such important entitlements as Social Security and Medicare, which are very important resources for Missouri counties and regions. Many over age 65 have retired from full-time employment and that has important implications for the economy, work force, housing, etc. Thus the population from age 65-84 is combined into one group.

  • Pre-school and School Age Children: It has also become common place to refer to pre-school and school age children as an important age related cluster of the population. The size of the pre-school and school age populations greatly influences the need for educational and health-related services. Thus the population age 5-17 is combined into one school-aged group.

  • Baby Boom Generation: In addition to those traditionally important age cohorts, seniors and school age children, an additional age cohort has acquired a name and produced great public policy, economic and life style affects over the past 35 years. This cohort, generally referred to as the baby boom generation, refers to the exceptionally large population cohort resulting from the unusually high birth rate from the end of World War II to the mid-1960s. The baby boom generation now spans two population groups - age 35-44 and 45-54 the reason for combining those groups into one.


This file last modified Thursday May 07, 2009, 14:37:22

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