For a detailed historical analysis of the risk that poorly designed income support schemes can cause unemployment rates to ratchet up from one recession to the next, see Chapter 4 in OECD (2003a). Past recessions have shown that both macro and labour market policies are required to offset persistence effects that would otherwise convert some portion of a cyclical increase in unemployment into higher structural unemployment. Hysteresis effects following a cyclical upsurge of unemployment during a recession appear to be closely associated with increases in long-term unemployment (Ball, 2009, Guichard and Rusticelli, 2010). At the individual level, the progressive loss of human capital, health and morale associated with extended periods of joblessness can reduce the attractiveness of these workers to potential employers. At the aggregate level, the unemployment rate associated with a stable rate of inflation (the so-called NAIRU) tends to rise with the size of the pool of the long-term unemployed, since their relative disconnection from the labour market means that they have little impact in restraining inflationary wage pressures.