Child labour refers to the employment of children in any work that deprives children of their childhood, interferes with their ability to attend regular school, and that is mentally, physically, socially or morally dangerous and harmful. This practice is considered exploitative by many international organisations. Legislations across the world prohibit child labour. These laws do not consider all work by children as child labour; exceptions include work by child artists, supervised training, certain categories of work such as those by Amish children, some forms of child work common among indigenous American children, and others.Child labour was employed to varying extents through most of history. Before 1940, numerous children aged 5–14 worked in Europe, the United States and various colonies of European powers. These children worked in agriculture, home-based assembly operations, factories, mining and in services such as newsies. Some worked night shifts lasting 12 hours. With the rise of household income, availability of schools and passage of child labour laws, the incidence rates of child labour fell.In developing countries, with high poverty and poor schooling opportunities, child labour is still prevalent. In 2010, sub-saharan Africa had the highest incidence rates of child labour, with several African nations witnessing over 50 percent of children aged 5–14 working. Worldwide agriculture is the largest employer of child labour. Vast majority of child labour is found in rural settings and informal urban economy; children are predominantly employed by their parents, rather than factories. Poverty and lack of schools are considered as the primary cause of child labour.The incidence of child labour in the world decreased from 25% to 10% between 1960 and 2003, according to the World Bank. Nevertheless, the total number of child labourers remains high, with UNICEF and ILO acknowledging an estimated 168 million children aged 5–17 worldwide, were involved in child labour in 2013.