Volatile Top Income Shares in Switzerland? Reassessing the Evolution Between 1981 and 2008

We study the recent evolution of top incomes in Switzerland. We close the data gap between 1993 and 2003 exploiting the fact that cantons changed their tax system at different points in time which allows us to use the non-changing cantons as control group. The results show that the share of top incomes has risen, the top 0.01% share even doubled in the last 20 years. However, top incomes exhibited large variation in the business cycle. We compare the results with social security data on top labor incomes for which the top shares can be measured precisely over the whole time span. The comparison confirms our initial findings and suggests that labor incomes have become more important among top income earners.