The main reason for this is that, as currently defined, the fiscal impoverishment indicator of the authors is based on a given poverty line, whereas shared prosperity is determined by following a distribution of income within a country. As a result, the bottom 40 percent of a population may be below a chosen poverty line in one country, while in another population, only a fraction of the bottom 40 percent will be below the same line.

However, the measures proposed in this paper can be used to assess the relationship between fiscal impoverishment and shared prosperity among different socioeconomic groups within a country as well as in comparing a group of countries. Indeed, these measures consider the experience of every single individual in an economy, and they allow researchers to compare fiscal losses among specific population subgroups, especially different quantiles (such as the bottom 40 percent), both within a country and among a group of countries.

# **6. Conclusion**

In this paper, the main focus has been on measuring the various dimensions of the fiscal losses and gains of a given fiscal system. We are proposing a family of measures that can accurately assess the extent to which a population is fiscally impoverished or fiscally enriched after the intervention of a fiscal system. This set of indicators addresses the incidence, intensity, and severity of fiscal losses and gains. An empirical illustration using the 2014 household consumption data in Niger, and contrasting the conclusions drawn based on current measures used in the literature with the new measures proposed here provides evidence of the benefits of these new measures.

The findings reveal that the incidence and the intensity of fiscal losses in Niger were 33.2 percent and 0.014, respectively; whereas those of fiscal gains were 66.8 percent (incidence) and 0.126 (intensity) in Niger. This suggests that overall the fiscal system is improving the welfare of the Nigerien population. Comparing the experience of the prefiscal poor to that of the prefiscal nonpoor, we found that the poor are more favored by the fiscal system. Fiscal losses are lower, and fiscal gains are higher in the subpopulation of prefiscal poor.

In contrast to current measures used in the literature, according to which people living in rural areas benefit more from fiscal gains, we find that the incidence and the intensity of fiscal gains are higher in urban areas when considering the situation of every Nigerien. Besides, while looking at the experience of the prefiscal poor or the prefiscal nonpoor alone, the results show that the incidence and the intensity of fiscal gains are greater in urban areas for both subpopulations. These findings show that people living in urban areas in Niger are likely benefiting the most in terms of fiscal gains in the country.

This paper can be extended along several dimensions of research. One natural extension would be to apply the measures developed here to identify the specific subgroups that are the most affected by a fiscal system within a country. These measures could also be readily applied to comparing fiscal losses and gains among any group of countries, regardless of their development level. Another avenue for future research is application of the measures proposed in this paper to discriminate among different fiscal reforms. A given fiscal reform may not improve the welfare of everyone in the country: some will be better off, while others will be worse off with the implementation of the reform. A rule for choosing the specific fiscal reform to implement among a group of reforms may be the one that will have the least amount of fiscal impoverishment and 19