Retail staff and teachers are among the unhappiest workers in the UK when it comes to their pay, according to a survey.
A study by jobs search engine Adzuna found that some of the happiest workers are those in human resources, consultancy and construction.
The survey of 1,000 workers found that two out of five workers believed they were paid less than their colleagues, while only a fraction (6%) thought they were paid more.
More than half (53%) admitted they have no idea of their true value to employers, and said they would never discuss salaries with a co-worker.
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As a result, just 13.6% said they had successfully lobbied their boss for a pay rise.
Workers in their 20s were more confident in their levels of pay, while those aged 35-44 were most insecure.
“British workplaces are rife with uncertainty over pay,” said Adzuna co-founder Doug Monro.
“An ingrained lack of transparency over earnings and salary bandings has created a culture of conviction others must be paid more than us.
“Combined with a lack of knowledge of what our own skills are worth to employers in today’s job market, this spells a recipe for disaster for ambitious career builders.”
Official data from the Office of National Statistics earlier this month pointed to the lowest jobless rate since 1975 – but wage growth remained stubbornly slow at 2.1%.