By contrast, fewer than half of all workers said they smile during the working day. The most unhappy are in manufacturing, where only 18 per cent find anything to smile about. Half of public sector workers and 61 per cent of marketing executives smile on the job. Teachers were not surveyed.
Tina Bruce, professor of early years education, said: "When you work with young children, you feel you're contributing to a vision of how you want the world to be. And young children are fundamentally good. They make you believe in humanity. That's incredibly uplifting."
The survey found that early years workers were the most altruistic, with 88 per cent claiming that job satisfaction was more important than financial reward. Two-thirds of all other employees preferred a fulfilling job to a good salary. And only 30 per cent of early years workers said that they had ever regretted their choice of career, compared with 50 per cent overall.
Stuart Milne, the deputy manager of Tawny nursery in Reading, is among them. "It's never going to be one of those high-earning jobs, so you have to have enthusiasm," he said. "But you are not just playing with children.
You are doing something that is vital to their development. Once you start the job, you see its possibilities."
The survey, carried out by the charity 4Children, was compiled following interviews with more than 1,000 employees, from sectors including banking, retail and healthcare.
Anne Longfield, the chief executive of 4Children, said: "Early years workers make a real difference to a child's life and can help shape their future."