La dynamique de pauvreté au Burkina Faso revisitée : pauvreté durable et transitoire, et vulnérabilité

The study explores the dynamics of the welfare of the households in Burkina Faso during1990's, based on an ex ante dissociation of the forms of poverty related to the vulnerability – the ex ante risk that a household is poor ex post, if it is not poor, or that he remains poor, if it is already poor. Econometric analysis, based on cross-section data, and admitting that thevariance of the residuals of the determinants of the expenditure per capita of the households isexplained by the observable characteristics of the latter, allows to identify six segments of the distribution of the households in terms of the vulnerability to poverty: (i) durable poor; (ii) transient and involutive poor; (iii) transient and evolutive poor; (iv) vulnerable and precarious non-poor; (v) vulnerable non-poor, and; (vi) non-poor. This stratification shows that: (i) the vulnerability of the households is a situation much more widespread than poverty –46,6 and 34,5 percent, respectively; (ii) durable poverty is the most significant component of poverty – 57,6 percent; (iii) categories of non-poor households seems particularly exposed to the risk of poverty – 20,6 percent. The study balances the stability of the total poverty, notedbetween 1994-95 and 1998, while observing: (i) a progression of the proportion of very vulnerable households; (ii) a rise of durable poverty; (iii) an increase of the proportion of certain non-poor households strongly exposed to the risk of short-term poverty. From this situation results a growing number of vulnerable households because of a weakness of the expenditure per capita, and a decline of the relative importance of the families of which the vulnerability is inherent in a variability of the expenditure per capita – conclusions refined by the consideration of the areas and the labour market statutes. In addition, the study highlights several other lessons. Firstly, the growth of the average probability of national poverty of the households – 7,1 percent –, associated with almost unchanged indices of poverty, is heterogeneous: strong growth in the cities and weak increase in the rural sector. Secondly, among the sources of the vulnerability – compared to a reference household –, the effect of the expected expenditure dominates the effect of the variance at the national level – at a given time or during the period –, but is balanced in urban areas, compared to the rural zones. Lastly, using spatial data, research shows that: (i) the log of the ratio between the vulnerability and poverty grows with the provincial urbanization ; (ii) rates of durable and transient poverty are conversely correlated with the urbanization. These conclusions encourage to explore the effects of the structural and demographic changes on poverty and the vulnerability, with a logistic multinomial model. In particular, the analysis of sensitivity highlights the impact of a whole of factors inherent in the head of household or the group: instruction, age, sex, ethnicity, demography of the household, labour market statutes, rate of employment by household, transfers, migration, spatial localization. Finally, the effectiveness of the policies of fight against poverty is questioned in the absence of an integration at once of the temporal dimension of the welfare of the households, and taking into account of non-poor groups, but strongly exposed to the risk of short-term poverty. (Full text in French)