However, the economy eventually hits an "inflation barrier" that is imposed by the four other kinds of unemployment to the extent that they exist. Historical experience suggests that low unemployment affects inflation in the short term but not the long term. In the long term, the velocity of money supply measures such as the MZM ("money zero maturity", representing cash and equivalent demand deposits) velocity is far more predictive of inflation than low unemployment.Some demand theory economists see the inflation barrier as corresponding to the natural rate of unemployment. The "natural" rate of unemployment is defined as the rate of unemployment that exists when the labour market is in equilibrium, and there is pressure for neither rising inflation rates nor falling inflation rates. An alternative technical term for that rate is the NAIRU, the Non-Accelerating Inflation Rate of Unemployment. Whatever its name, demand theory holds that if the unemployment rate gets "too low," inflation will accelerate in the absence of wage and price controls (incomes policies). One of the major problems with the NAIRU theory is that no one knows exactly what the NAIRU is, and it clearly changes over time. The margin of error can be quite high relative to the actual unemployment rate, making it hard to use the NAIRU in policy-making.Another, normative, definition of full employment might be called the ideal unemployment rate. It would exclude all types of unemployment that represent forms of inefficiency.
Additional data are also available from the government, such as the unemployment insurance weekly claims report available from the Office of Workforce Security, within the U.S. Department of Labors Employment and Training Administration. The Bureau of Labor Statistics provides up-to-date numbers via a PDF linked here. The BLS also provides a readable concise current Employment Situation Summary, updated monthly. The Bureau of Labor Statistics also calculates six alternate measures of unemployment, U1 to U6, which measure different aspects of unemployment:
U1: Percentage of labor force unemployed 15 weeks or longer. U2: Percentage of labor force who lost jobs or completed temporary work. U3: Official unemployment rate, per the ILO definition, occurs when people are without jobs and they have actively looked for work within the past four weeks. U4: U3 + "discouraged workers", or those who have stopped looking for work because current economic conditions make them believe that no work is available for them. U5: U4 + other "marginally attached workers," or "loosely attached workers," or those who "would like" and are able to work but have not looked for work recently. U6: U5 + Part-time workers who want to work full-time, but cannot for economic reasons (underemployment).Note: "Marginally attached workers" are added to the total labour force for unemployment rate calculation for U4, U5, and U6. The BLS revised the CPS in 1994 and among the changes the measure representing the official unemployment rate was renamed U3 instead of U5.