They were originally developed by the National Readership Survey (NRS) to classify readers, but have since been used by many other organisations for wider applications and have become a standard for market research.
[1] They were developed in the late 1950s and refined in following years and achieved widespread usage in 20th century Britain.
[3] The distinguishing feature of the NRS social grade is that it is based on occupation, rather than income, wealth or property ownership.
[5] Only around 2% of the UK population identifies as upper class,[6] and this group is not separated by the classification scheme.
The grading system is also sometimes used in the Republic of Ireland with the addition of a Class F signifying Farmers and Agricultural Workers.