New research suggests that most US presidents will be largely forgotten within 50-to-100 years of their serving as president, based on presidential-recall tests given to three generations of undergraduate college students (1974, 1991 and 2009) and 577 adults ages 18-69 in 2014.

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New research suggests that most US presidents will be largely forgotten within 50-to-100 years of their serving as president, based on presidential-recall tests given to three generations of undergraduate college students (1974, 1991 and 2009) and 577 adults ages 18-69 in 2014.