Inkomstindexet

Inkomstindexet is a statistical concept used to describe changes in income levels over time, primarily within Swedish statistical and policy contexts. It provides a way to monitor living standards and the redistributive effects of fiscal measures by tracking how income evolves across the population.

There is no single universal definition of Inkomstindexet; in practice, researchers and government agencies construct the index from data on household incomes. Common approaches use equivalized disposable income (income after taxes and transfers adjusted for household size) to enable comparability across households. The index is typically presented with a base year set to 100, with subsequent years showing relative changes. It can be based on mean income or median income, with median often preferred to reduce the impact of very high incomes. When prices are taken into account, a real income index is obtained by deflating nominal incomes with a price index, such as the consumer price index (CPI).

Uses of Inkomstindexet include evaluating living standards, analyzing the effects of tax reforms and transfer programs, and informing policy discussions. It may also be used to define thresholds for social benefits or to calibrate relief measures. The index is published at various levels of disaggregation—national, regional, or by demographic groups—and is commonly presented alongside other indicators of income distribution, such as poverty lines or the Gini coefficient, to provide a fuller picture of changes in economic well-being.

Limitations include dependence on data sources and methodological choices (for example, mean versus median, or the choice of equivalence scales) and potential breaks due to policy changes that affect taxable income. While most commonly discussed in Swedish statistical and policy literature, the concept of an income index is also recognized in broader comparative research on living standards and income distribution.