sentations of county-level mortality data from 1997–2001 show how life expectancy rates for men (ranging from age 62.0 to age 80.2) and women (ranging from age 71.8 to age 84.5) vary depending on an individual’s county of birth (Figure 2-1). Like a mosaic, the shades depicting different life expectancy rates appear random and unrelated at first; however, further examination reveals that mortality patterns seem to follow specific geographic patterns.

Data comparing county-level life expectancy rates for men and women over time can be examined in several ways. Figure 2-2 shows the standard deviation of the distribution of life expectancy across counties for men and women between 1960 and 2000. Although the lines depicting the standard deviation of county life expectancies for men and women follow similar trajectories, the differences across counties began to steadily increase after 1980.

Similarly, tracking life expectancies for counties in the top and bottom 2.5 percentiles over time for men and women shows a similar result (Figure 2-3). Although the gap in life expectancies for the counties in the top and bottom 2.5 percent of all U.S. counties remained fairly constant from 1960 until around 1980, it has been growing since that time. Among the bottom 2.5 percent of counties, little or no progress in increasing life expectancies has been seen over the past 20 years. In absolute terms, the differentiation in life expectancies in U.S. counties continues to widen.

According to the U.S. national average, and as seen in data from counties that have historically had the highest life expectancies, male life expectancy has been increasing faster than female life expectancy. The counties with the highest life expectancies in the United States are at levels that surpass those seen in Japan, the country with the highest life expectancies globally.

Defining the Eight Americas

In addition to summarizing county-level analysis, race-counties—referring to the county of death and the race of the deceased—were analyzed using 5-year moving averages. Life expectancies were calculated for race groups in every county where mortality among members of a certain race was large enough for the analysis. Data show that the range of life expectancies seen in the United States is even larger when comparing race-counties. Life expectancies as low as 58 years of age were calculated for Native Americans in southwestern South Dakota, and Asian women in Bergen County, New Jersey, have average life expectancies reaching 91 years of age. There is no evidence that the magnitude of the gaps is closing.

Further analysis was conducted using the amassed county and race-county data to identify which diseases accounted for the existing mortality

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