During this period, the share of first- and second-generation immigrants in the population increased from around 6 per cent in 1993 to over 24 per cent in 2022. We categorize immigrants into three broad country groups, while the rest of the population is classified as non-immigrants. Our analysis consists of three parts: (a) calculating inequality with and without immigrants, (b) decomposing inequality within and between country groups, and (c) assessing the isolated effect of changes in the share of each group since1993.
The impact of excluding immigrants from the calculation of the Gini coefficient for household income after taxes has increased over time. If we exclude first-generation immigrants, the Gini coefficient today is about1.5 percentage points lower than when including them, compared to a difference of only 0.5 percentagepoints in 2005. Across all our analyses, we find that inequality within country groups—rather than betweenthem—accounts for most of the overall Gini coefficient, although the between-group component has grown over time. We also find that the rise in the share of immigrants from broadly defined country groups has,on its own, contributed to an increase in income inequality of about 1 percentage point since 1993. For comparison, the Gini coefficient for household income after taxes increased by 2 percentage points from1993 to 2022.
When looking specifically at market income or at households in Oslo, we find a more varied picture of how immigration affects income inequality. However, the key conclusion remains that changes in income within and between immigrant groups, rather than the size of these groups, are the main drivers of changes in inequality since 1993.
This report does not consider the potential effects of increased immigration on income and employment for other groups. Therefore, the analysis does not provide a complete picture of how immigration has influenced income inequality in Norway.