Comparability

Comparability - geographical

The taxation systems differ widely across countries, which makes the comparison difficult because of conceptual and computational differences. The main purpose of national statistics is normally not to accommodate international comparison, but to accommodate each country's own information setup and traditions.

The taxation in Denmark differs widely from all other European countries. In Denmark, contribution to social security schemes constitutes an exceptionally small share of total taxation, whereas income taxes account for more than 60 percent. This is in contrast to most other European countries where the contribution to social security schemes constitute a particular high share of the total taxation and income taxes only constitute a minor percentage. Among the OECD countries, only New Zealand and Australia have a tax structure that is to some extent similar to the Danish one.

Comparability over time

From when the Danish income tax was first introduced in 1903 and until the tax reform in 1987 the valid principle was that the taxable income – that is gross income minus deductions – was taxed according to the same tax scale. However, with the tax reform in 1987, the uniform tax principle was broken as both income and deduction concepts changed. The concept change makes it very difficult to compare the income taxes before and after the reform in 1987. The current structure for Danish income taxes means that the numbers are split into personal, capital income, and deductions. Before the tax reform, the number were split into gross income and deductions.

For the income years from 1987 - 2016, the assessment of personal income taxes based upon datasets from July just 1½ year after the income year. The datasets from these years are considered final and the final data are not grossed up. From 2017, both preliminary and final data are grossed up.

Coherence - cross domain

Not relevant for these statistics.

Coherence - internal

Not relevant for these statistics.