without work during the reference week; available to start work within the next two weeks (or has already found a job to start within the next three months); actively having sought employment at some time during the last four weeks." The labour force, or workforce, includes both employed (employees and self-employed) and unemployed people but not the economically inactive, such as pre-school children, school children, students and pensioners. The unemployment rate of an individual country is usually calculated and reported on a monthly, quarterly, and yearly basis by the National Agency of Statistics. Organisations like the OECD report statistics for all of its member states. Certain countries provide unemployment compensation for a certain period of time for unemployed citizens who are registered as unemployed at the government employment agency. Furthermore, pension receivables or claims could depend on the registration at the government employment agency. In many countries like in Germany, the unemployment rate is based on the number of people who are registered as unemployed. Other countries like the United States use a labour force survey to calculate the unemployment rate. The ILO describes four different methods to calculate the unemployment rate: Labour Force Sample Surveys are the most preferred method of unemployment rate calculation since they give the most comprehensive results and enables calculation of unemployment by different group categories such as race and gender. This method is the most internationally comparable. Official Estimates are determined by a combination of information from one or more of the other three methods. The use of this method has been declining in favor of labour surveys. Social Insurance Statistics, such as unemployment benefits, are computed base on the number of persons insured representing the total labour force and the number of persons who are insured that are collecting benefits. This method has been heavily criticized because if the expiration of benefits before the person finds work. Employment Office Statistics are the least effective since they include only a monthly tally of unemployed persons who enter employment offices. This method also includes those who are not unemployed by the ILO definition. The primary measure of unemployment, U3, allows for comparisons between countries. Unemployment differs from country to country and across different time periods. For example, in the 1990s and 2000s, the United States had lower unemployment levels than many countries in the European Union, which had significant internal variation, with countries like the