The Emergence and Consolidation of Microsimulation Methods in France

[eng] The purpose of this paper is to trace the gradual emergence of microsimulation models dedicated to the analysis of tax and social security policies in France since the mid-1960s, as well as their subsequent consolidation since the mid-2000s. A brief outline of these models is given using the static/dynamic distinction. A connection is made between the construction of the Mir model (standing for Modele de l'impot sur le revenu, an income tax model) and the development of the Household income survey Revenus fiscaux. Then we distinguish two periods: An initial period that saw a proliferation of such models and a second period, of standardisation, during which the Ines model has acquired a central position. Besides ongoing evaluations (of minimum income and pension schemes, insurance for long-term care), the most recent expectations in this area relate to the ex ante evaluation of measures designed to accelerate the ecological transition and of universal income -type schemes. Finally, we underline that the recent replacement of all the periodic declarations made by employers to various administrations by a unique declaration (the Declaration sociale nominative, or DSN) significantly renews the range of administrative sources capable of feeding into these models.