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Looking at Predictions with Hindsight

Consider these percentages of people age 65 who are expected to survive to age 90:

  • 1940: 7%
  • 1960: 14%
  • 1980: 25%
  • When this data was analyzed, the projected values for the years 2000 and 2050 were 26% and 42% respectively.

    Question 1: Given the considerable changes over previous 20-year periods, why do you think there was a change of only 1% from 1980 to 2000? (Note: The prediction perhaps was made in 1997?)

    Question 2: Given the data above, what would be your projected values for the years, 2000, 2010, 2020, and 2050? Explain.

    And a note to ponder: Of all the people in human history who ever reached the age of 65, half are alive now.

    Source: "The Old Get Older," The Ann Arbor News, February 25, 1997, p. A1