Background: Four principles are used to distribute payments via the Swedish social-insurance system in cases of temporary or permanent illness and death. This paper studies the redistributive effects on income of these four principles.
Methods: The analysis is based on aggregate social-insurance data from the 25 municipalities that comprise Stockholm County in Sweden. For nine different types of social-insurance payments based on the four principles, the degree of income redistribution is measured according to concentration indexes and differences between Gini coefficients with social-insurance payments excluded and included.
Results: The concentration indexes for payments from the nine social-insurance schemes in total is -0.0469. The Gini coefficient falls from 0.0437 excluding insurance payments (i.e. for income only from gainful work, IGW) to 0.0379 when including insurance payments with income from gainful work (IGW + TP). That is, the Gini coefficient is 15% lower when insurance payments are included. Decomposition by payment shows that the largest redistribution effect on income inequality is made by disability pension.
Conclusion: Municipalities with low average income are favoured by the Swedish social-insurance system. Payment principles can be ranked according to their redistributive capacity: mix of compensating-lost-income and flat-rate, compensating-lost-income, means-testing, flat-rate, and need-based respectively. The nine social-insurance schemes contribute very differently to income redistribution. Disability pension and sickness allowance contribute most to income redistribution and reducing income inequality.