Okun’s law in the US and the employment crisis in Germany

What is Okun’s law? Arthur M. Okun (1928-80), an American economist and long-time member of the US Council of Economic Advisors published in 1962 a paper which made a statement about a stable macroeconomic relation between the change of the unemployment rate and the growth rate of real output for the US economy, measured by the gross domestic product, i.e.