Final answer:
The question involves categorizing individuals under age 65 born in even-numbered years using U.S. Census Bureau data and related demographics. It touches upon the impact of the aging Baby Boomer population and their eligibility for Medicare with a demographic evenly spread across cohorts.
Step-by-step explanation:
The question is asking to categorize individuals under the age of 65 who were born during an even-numbered year. To address this, we can examine the U.S. Census Bureau data and population surveys that offer insight into age demographics and trends. For instance, those born in the years listed (1964, 1968, 1972, 1976, 1980, 1984, 1988, 1992, 1996, 2000) fall within the age categories of 18 to 24 years, 25 to 44 years, and 45 to 64 years during various time periods.
Given the information provided, it is also important to consider the context of aging populations, such as the Baby Boomers Come of Age phenomenon. In 2013, it was reported that 20% of the U.S. population was over 60 years old. This indicates that a significant number of individuals born in even-numbered years are approaching or have reached an age where they may require increased medical care, and many are or will soon be eligible for Medicare.
The distribution of births being approximately uniform over the span of a year indicates that individuals are likely to be born in any given week, thereby supporting a uniform age distribution across cohorts born in even-numbered years under the age of 65. This evenly spread out distribution, as well as the participation rate of various age groups in activities like voting, reflects the diversity of this demographic and the impact they have on society.