The non-labour force includes those who are not looking for work, those who are institutionalized (such as in prisons or psychiatric wards), stay-at-home spouses, children not of working age, and those serving in the military. The unemployment level is defined as the labour force minus the number of people currently employed. The unemployment rate is defined as the level of unemployment divided by the labour force. The employment rate is defined as the number of people currently employed divided by the adult population (or by the population of working age). In these statistics, self-employed people are counted as employed.