Explanation:

Any unemployment not considered to be natural is often referred to as cyclical, institutional or policy-based unemployment. Variables exogenous to the labor market cause an increase in the natural rate of unemployment; for example, a steep recession might increase the natural unemployment rate if workers begin to lose skills or the motivation to find full-time work again. Economists sometimes call this “hysteresis.” Important contributors to the theory of natural unemployment include Milton Friedman, Edmund Phelps and F.A. Hayek, all Nobel winners.