Defining and measuring unemployment is a complex business, heavily dependent on the criteria used. Indeed the boundaries between employment, unemployment and inactivity are not always easy to define (take for example a student who works a few hours per week).
The International Labour Office (ILO) has, however, provided a strict definition of unemployment, which does not take into account various interactions which may exist with employment (occasional work, underemployment), or crossover with inactivity: indeed, some people wish to work but are ‘classed’ as being inactive either because they are not immediately available to work (within two weeks) or because they are not actively seeking work).
People who fall into these categories form what is known as a ‘halo’ around unemployment.
This ‘halo’ is calculated by INSEE on the basis of the Employment Survey.