The Effectiveness of Fiscal Stimuli for Working Parents *To promote the labor participation of parents with young children, governments employ a number of fiscal instruments. Prominent examples are childcare subsidies and in-work benefits. However, which policy works best for employment is largely unknown. We study the effectiveness of different fiscal stimuli in an empirical model of household labor supply and childcare use. We use a large and rich administrative data set for the Netherlands. Largescale reforms in childcare subsidies and in-work benefits in the data period facilitate the identification of the structural parameters. We find that an in-work benefit for secondary earners that increases with income is the most effective way to stimulate total hours worked. Childcare subsidies are less effective, as substitution of other types of care for formal care drives up public expenditures. In-work benefits that target both primary and secondary earners are much less effective, because primary earners are rather unresponsive to financial incentives. JEL Classification:C25, C52, H31, J22

This paper presents a structural labour supply model for the Netherlands. The model uses a large, rich data set which allows for precise estimates of labour supply elasticities for several subgroups. We use an advanced tax benefit calculator to calculate households' budget constraints accurately. Both the large, rich data set and the advanced tax benefit calculator enable us to perform more accurate policy predictions. Simulations show that labour supply elasticities differ among subgroups. Labour supply elasticities for men in couples are low but labour supply elasticities are much higher for cohabiting/married women. Furthermore, elasticities are relatively high for individuals with a lower education and/or non-Western background. Policy simulations provide two important insights. First, an introduction of either a pure flat tax, or an income-neutral flat tax, decreases aggregate labour supply. Second, an EITC for working parents is more effective in stimulating aggregate labour supply than an EITC for all workers or an overall reduction in marginal tax rates.

A related literature studies the elasticity of taxable income to measure the distortions of taxation (Saez et al., 2012a). However, there is an active debate on whether the elasticity of taxable income is a sufficient statistics to measure the distortions from taxation (Chetty, 2009). The views expressed in this chapter do not necessarily reflect the position of CPB Netherlands