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Over 25 years, the time devoted to sleep remained stable, except among older adults, whose sleep time decreased. Its place in daily routines did not remain fixed, however. Bedtimes moved progressively later, partly due to the growing popularity of evening TV programmes that kept viewers up for longer. Time devoted to sleep is socially structured. Sleep time is linked to gender and occupation. The impact of children on sleep time was stronger for women than for men. Being in employment reduced sleep time, but its effect was not the same for all occupational categories; it was manual workers whose sleep time varied the most between working and non-working days. After retirement, the social differentiation in sleep time persisted, as the sleep patterns acquired during working life remained unchanged. Retirees formerly in higher-level or intermediate occupations slept less than farmers and manual workers.