All persons aged at least 15 who have their residence in the Federal Republic of Germany (national concept) and who exercise or seek an activity directly or indirectly geared towards earning money (dependent employees, self-employed, family workers), irrespective of the importance of the income from this occupation for their livelihood and not considering the working time actually performed or to be contractually performed (concept of gainful employment). The labour force is comprised of employed and unemployed persons.