In their latest paper, Anna Almosova, NOUS member Michael C. Burda and Simon Voigts investigate business cycle dynamics of social security contributions (SSC), by far the largest labor tax distortion in the OECD. In most countries, they find a negative covariation of SSC tax burdens with levels and growth of GDP at business cycle frequencies and lower. In detrended data, a decline of GDP of 1% is associated with a 0.05-0.2 percentage point increase in the aggregate SSC burden, measured as a fraction of the wage bill. For most countries, average marginal SSC rates exceed, but track average rates. Changes in average SSC tax burdens are largely due to adjustments in statutory tax schedules rather than cyclical shifts in earnings distributions. Their findings are consistent with Esping-Andersen’s (1990) typology of social welfare states. In some countries, SSC rates co-move with measures of the “labor wedge”.