Table 3.11 and Figure 3.1 show the average tax wedge (combined burden of income tax, employee and employer social security contributions) taking into account the amount of cash benefits each specific household type is entitled to. Total taxes due minus transfers received are expressed as a percentage of labour costs, defined as gross wage plus employers’ social security contributions (including payroll taxes). In the case of a single person on average wage the tax wedge ranges from 7.0% (Chile) and 18.4% (New Zealand) to 49.5% (Germany) and 52.7% (Belgium). For a one-earner married couple, with two children, at the same wage level the tax wedge is lowest in New Zealand (1.9%) and Chile (7.0%) and highest in Italy (39.1%) and France (39.4%). As stated in Chapter 1, the tax wedge tends to be lower for a married couple, with two-children, at this wage level than for a single individual without children due to both receipt of cash benefits and/or more advantageous tax treatment. It is also interesting to note that the tax wedge for a single parent, with two children, earning 67% of the average wage is negative in New Zealand (-20.5%), Canada (-15.2%), and Poland (-12.0%). This is due to the amount of cash benefits received by these families plus any applicable non-wastable tax credits that exceed the sum of the total tax and social security contributions that are due.
Table 3.2 and Figure 3.2 present the combined burden of the personal income tax and employee social security contributions, expressed as a percentage of gross wage earnings (the corresponding measures for income tax and employee contributions separately are shown in Tables 3.4 and 3.5). A single person at the average wage level without children has the highest average tax plus contributions burden in Belgium (39.8%). The lowest average rates were in Chile (7.0%), Mexico (10.2%), Korea (14.9%), Estonia (15.0%), Switzerland (17.4%), Israel (18.1%) and New Zealand (18.4%).
Table 3.3 shows the combined burden of income tax and employee social security contributions, reduced by the entitlement to cash benefits, for each household type. Figure 3.3 illustrates this burden for single individuals without children and one-earner married couples with two children, with both household types on average earnings. Comparing Table 3.2 and Table 3.3, the average tax rates for families with children (columns 4 -7) are lower in Table 3.3because most OECD countries support families with children through cash benefits.
A lower burden is also observed for a single individual, without children, at 67% of the average wage in Canada because of a cash transfer paid to mitigate the burden imposed by the federal consumption tax (i.e. the Goods and Services Tax Credit; further details can be found in the country chapter contained in Part II of this Report). The same is true in Denmark for single taxpayers at 67% and 100% of the average wage and two-earner married couples, without children, at 133% of the average wage who receive a Green Check to compensate for increased environmental taxes.
Comparing Table 3.2 and Table 3.3, for single parents, with two children, earning 67% of the average wage, 30 countries provide cash benefits. In Poland, Canada and New Zealand these represent respectively 47.2%, 38.6% and 35.6% of income and they are at least 25% of income in Denmark (27.0%). 29 countries provide benefits for a one-earner married couple, with two children, earning the average wage level, although these are less generous relative to income, ranging up to 16.5% (Canada and New Zealand). The lower level of cash benefits for the married couple can be attributed to three reasons: single parents may be eligible for more generous treatment; the benefits themselves may be fixed in absolute amount; or the benefits may be subject to income testing.
Table 3.4 shows personal income tax due as a percentage of gross wage earnings. For single persons, without children, at the average wage (column 2) – the income tax burden varies between 0,01% (Chile) and 35.8% (Denmark). In most OECD member countries, at the average wage level, the income tax burden for one-earner married couples with two children is lower than that faced by single persons (compare columns 2 and 5). These differences are clearly illustrated in Figure 3.4. In nine OECD countries, the income tax burden faced by a one-earner married couple with two children is less than half that faced by a single individual (Germany, Hungary, Luxembourg, Poland, Portugal, the Slovak Republic, Slovenia, Switzerland and the United States). In contrast, there is no difference in eight countries – Australia, Finland, Israel, Lithuania, Mexico, New Zealand, Norway and Sweden. In Chile, the one-earner married couple at the AW level with children did not pay personal income tax.
There is only one OECD member country where a married average worker with two children has a negative personal income tax burden. This is due to the presence of non-wastable tax credits, whereby credits are paid in excess of the taxes otherwise due. This results in tax burdens of -5.1% in the Czech Republic. Similarly, single parents, with two children, earning 67% of the average wage show a negative tax burden in six countries – the Czech Republic, Germany, Israel, Poland, Spain and the United States. In two other countries – Chile and Hungary – this household type pays no income tax.
A comparison of columns 5 and 6 in Table 3.4 demonstrates that if the second spouse has a job which pays 33% of the average wage, the income tax burden of the household (now expressed as 133% of the average wage) is slightly higher in seventeen countries, the largest differences being in the Czech Republic (6.2 percentage points) and Germany (5.6 percentage points). At the same time, the income tax burden is lower in eighteen countries, the largest differences being in Finland (-5.0 percentage points), Australia (-4.3 percentage points) and the Netherlands (-4.0 percentage points). There is no impact on the tax burden in Chile.
An important consideration in the design of an income tax is the level of progressivity - the rate at which the income tax burden increases with income. A comparison of columns 1 to 3 in Table 3.4 provides an insight into the levels of progressivity in the income tax systems of OECD countries. Comparing the income tax burden of single individuals at the average wage level with their counterparts at 167% of the average wage (columns 2 and 3), the lower paid worker faces a lower tax burden in all countries except in Hungary. There, a flat tax rate is applied on labour income and all households without children pay the same percentage of income tax. The same is true for single individuals at 67% of the average wage level compared with their counterparts at the average wage level. Finally the burden faced by single individuals at 67% of the average wage level represents 25% or less of the burden faced by their counterparts at 167% in four OECD countries: Chile (0%), Mexico and the Netherlands (both 24%) and Korea (25%).
The addition of social security contributions to the average tax rate reduces this progressivity as well as the proportional tax savings (i.e. tax savings of the low income workers relative to the higher income workers). When comparing Table 3.2 with Table 3.4, the OECD personal average tax burden of single individuals at 67% of the average wage level is only 32% lower than their counterparts at 167% compared to the OECD average tax savings of 47% for personal income taxes alone. The OECD average tax savings observed for one-earner married couples with two children at the average wage level relative to the average single workers falls from 34% to 21%. These lower figures reflect that there is little variation between social security contribution rates across household types, as shown in Table 3.5.
Table 3.5 shows employee social security contributions as a percentage of gross wage earnings. For a single worker without children at the average wage (column 2) the contribution rate varies between zero (Australia, Denmark and New Zealand) and 22.1% (Slovenia). Australia, Denmark and New Zealand do not levy any employee social security contributions paid to general government and there are three other countries with very low rates - Iceland (0.3%), Mexico (1.4%) and Estonia (1.6%). Social security contributions are usually levied at a flat rate on all earnings, i.e. without any exempt threshold. In a number of OECD member countries a ceiling applies. However, this ceiling usually applies to wage levels higher than 167% of the average wage. The flat rates result in a constant average burden of employee social security contributions for most countries between 33% and 167% of average wage earnings. Constant proportional burden for employee social security contributions for over the eight model household types, is observed in (in decreasing order of rates) Slovenia (22.1%), Poland (17.8%), Greece (16.0%), Turkey (15.0%), the Czech Republic, Latvia and Portugal (all 11.0%), Finland (9.8%), Lithuania (9.0%), Norway (8.2%), the United States (7.7%), Chile (7.0%), Spain (6.4%), Switzerland (6.2%) and Estonia (1.6%).
In addition, at the average wage level only Germany and the Netherlands impose different burdens of social security contributions on employees according to their family status (see Figure 3.5).
