The United Nations Classification of the Functions of Government (COFOG), which is a classification by socioeconomic objective and is used for the formulation of public policy and international comparison. A functional classification is stable and independent of the administrative structure.
The COFOG has three levels of detail: directorates, groups, and classes. The first level contains 10 two-digit categories called directorates, covering for example general public services (directorate 01) or education (09). Groups and classes give details on the means by which the general objectives are to be achieved.
Each directorate comprises several three-digit groups: for example, foreign economic aid (012) or pre-primary and primary education (091). Lastly, each of these groups contains one or more four-digit classes: the functioning of executive and legislative bodies (0111) and financial and fiscal affairs (0112).