In that happiness is believed to originate from a comparison of one’s current circumstances relative to past achievement, Iowa State University researchers have identified key predictors of happiness among the oldest old  (those ages 85 years and older). In a study of 158 Georgia centenarians, Alex Bishop and colleagues analyzed the subjects' responses to a series of questions that assessed their happiness, perceived health, social provisions, economic security and life satisfaction. While there was no indication that resources affect happiness, past life satisfaction -- even individual achievements -- was found to have a direct association.  In other words, past satisfaction with life -- even if something as simple as recalling isolated career accomplishments – was a major key to happiness in our oldest years. Suggesting that reminiscence therapy and structured life review sessions may be beneficial in fostering feelings of happiness among very old populations, the team concludes that: “Past satisfaction with life is directly associated with present happiness. This presents implications relative to understanding how perception of resources may enhance quality of life among persons who live exceptionally long lives.”