In any given month 4.4% of U.S. workers have major depression. Stress at work has been linked to an increased risk of depression and researchers at the University of Calgary in Canada have been looking into this link. They measured people's job stress in 1994-5 and again in 2000-1 and asked them about their levels of depression at the end of the study. They found that those who were under stress at both the start and the end of the study were twice as likely (8%) to be depressed as those who were under little stress at both times (4%). For people whose jobs got less stressful over the period of the study the depression rate was 4.4% while for those whose jobs got more stressful it was 6.9%.
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