the progressivity of statutory labour tax schedules including social security contributions has increased in the majority of countries since figure though there has been a steep decline in top marginal income tax rates a number of countries have cut social security contributions and introduced or strengthened inwork tax benefits targeted at lower incomes thus increasing the progressivity of labour taxes by contrast the use of tax expenditures which often benefit highincome groups most such as tax breaks for health and child care tertiary education owneroccupied housing and retirement savings has been growing oecd b