However, compared with the size of the programme and that of the labour force, this effect is not large.73 These findings may suggest that the programme was simply not sufficiently large during the early years of its implementation to have a significant impact on the share of informal employment. The impact of Seguro Popular is identified using a difference-in-differences estimator that exploits the staggered implementation across states. The analysis makes use of two different measures of programme supply: i) the actual share of households affiliated to Seguro Popular in the total, and ii) the targeted share of households, as agreed between the federal and state governements. The econometric analysis involves relating the within-state variation in the supply of Seguro Popular to the within-state variation in the incidence of informality conditional on any common macro-economic developments across states and various observable state characteristics (see Box 2.7).