Postdoctoral research fellow a the Center for Law and Economics, ETH Zürich

Affiliated researcher at Institut des politiques publiques and World Inequality Lab

I received my Ph.D. in June 2018 at the Paris School of Economics under the supervision of Pr. Thomas Piketty and Pr. Antoine Bozio.

Research interest: labor economics, empirical public economics

Contact information:
IFW E 44
Haldeneggsteig 4
8092 Zürich
Switzerland
malka.guillot[at]gess.ethz.ch

Curriculum vitae

My latest research

Who Paid the 75% Tax on Millionaires? Optimization of Salary Incomes and Incidence in France (latest working paper)

Using several administrative datasets, I study the impact of temporary tax on top wage income earners, implemented for 2013 and 2014 only and known as the "75% tax above 1m euro''. The tax is nominally paid by the firms. The tax base is gross annual salary income above one million euros and the top marginal tax rate on wage earners increased from 64% to 74% because of the tax. About 400 employers paid the tax each year and about 1000 employees were concerned. I document that the tax was largely borne by employers, who paid 80% of the tax. Taking advantage of the short term nature of the tax, I show that the tax triggered important optimization response of wage earners, taking the form of time-shifting. I do not see any income-shifting nor any migration response. I study the elasticity of the pre-tax labour income to the net-of-tax rate (1 minus the marginal tax rate) and find an elasticity of $0.3$, that I interpret as pure optimization. The firms were also affected by the tax through a decrease in the total number of employees and demonstrate some evidence of optimization behaviour.

Inequality and Redistribution in France, 1990-2018: Evidence from Post-Tax Distributional National Accounts, with Antoine Bozio, Bertrand Garbinti, Malka Guillot, and Thomas Piketty, WID.world WORKING PAPER SERIES N° 2018/10

This paper presents post-tax Distributional National Accounts (DINA) for France. That is, we combine national accounts, tax and survey data in a comprehensive and consistent manner to build homogenous annual series on the post-tax, post-transfer distribution of national income by percentiles over the 1990-2018 period, with detailed breakdown by age, tax and transfer categories. We come with three main findings. First, taxes and transfers reduce total income inequality by 23% on average in France over this period. This is significant, but less than in the US (34%). The reason why overall inequality is much smaller in France than in the US is entirely due to differences in pretax inequality rather than in secondary redistribution. Next, due to the large role of indirect taxes, social contributions, and income capital exemptions, the overall profile of taxation is structurally regressive in France, a feature that has been reinforced in 2017-2018. Third, monetary transfers benefit mostly older age groups in France, and leave unaffected the low relative position of younger age groups. These series are currently being extended to cover the entire 1900-2018 period and to better take into account in-kind transfers.

Primary inequality and redistribution through employer Social Security contributions: France 1976-2010
​With Antoine Bozio and Thomas Breda

This paper makes two simple points. First, labour demand depends on product wage or labour cost. Hence, demand-side explanations for the rise in inequalities such as skill-biased technical change and job polarization should be tested using data on labour cost and not net wage or posted wage. Contrary to previous studies, we find evidence of skill-biased technical change in France when we measure wage inequality in terms of labour cost. In that respect, France is no exception. Second, the French case provides a clear evidence that changes in taxation can have very significant effect in converting market inequalities into consumption or net wages inequalities. In France, net wage inequalities have decreased by about 10%, while labour cost inequalities have increased by 15% over the 1976-2010 period. This fact provides support both for the supporters of the skill-biased technical change explanations of the secular increase in wage inequalities, as well to those who believe that institutions could have significant impact on inequalities in disposable incomes.