A worldwide study of 2 million people from 80 different countries has found an extraordinarily consistent pattern in depression and happiness levels across the life cycle. The researchers found that happiness followed a U-shaped curve with happiness higher towards the start and end of people's lives and depression most common in the middle. The peak age for depression in the UK was 44. In the U.S. depression peaked at 40 for women and 50 for men and the same U-shaped curve held true for 72 other countries in the study irrespective of age, marital status, income and family status. The causes of the U-shaped curve are unclear although the researchers speculated that younger people had more hope while older people were better at counting their blessings.
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