Older people who have low expectations for a satisfying future may be more likely to live longer, healthier lives than those who see brighter days ahead, according to new research "Our findings showed that being overly optimistic in predicting a better future was associated with a greater risk of disability and death within the following decade," said Frieder R. Lang, the leading researcher of the University of Erlangen-Nuremberg in Germany." Pessimism  about the future may encourage people to live more carefully, taking health and safety measures." Lang and colleagues examined data collected from 1993 to 2003 for the national German Socio-Economic Panel, an annual survey on approximately 40,000 people from 18 to 96 years old. The researchers divided the data according to age groups: 18 to 39 years old, 40 to 64 years old and 65 years old and above. Through mostly in-person interviews, the participants were asked to rate how satisfied they were with their lives and how satisfied they thought they would be in five years. Five years after the first interview, 43 percent of the oldest group had underestimated  their future life satisfaction, 25 percent had predicted accurately and 32 percent had overestimated  , according to the study. The researchers calculated that each increase in overestimating future life satisfaction was related to a 9.5 -percent increase in reporting disabilities and a 10- percent increase in risk of death.  Because a darker outlook on the future is often more realistic, older adults' predictions of their future satisfaction may be more accurate, according to the study. In contrast, the youngest group had the sunniest outlook.  "We argue, though, that the analysis may depend on age and available resources. These findings shed new light on how our perspectives can either help us take action or prevent us from taking action that can help improve our chances of a long, healthy life," Lang said. Based on the passage, the researchers  _  .
collected 13 years of nationwide data calculated people's life satisfaction within five years interviewed 40,000 people from 18 to 65 years old divided the data into four age groups