Explaining the curve in the U-shaped curve

Abstract

In a previous paper we have demonstrated that for the total population of households, including non-givers, lower income households participate less and donate smaller average percentages of their household incomes than do higher income households. In this paper we inquire about the relative generosity of that sub-population of households that actually donate to charitable causes. We base our analysis on data collected in the 1990 national survey of Giving and Volunteering in the United States conducted by the Gallup Organization for Independent Sector. In the first section we review the factors that differentiate the upward sloping curve describing the population of all households and the U-shaped curve describing the sub-population of contributing households. In the second section we demonstrate that a substantial proportion of the curvature in the U-shaped relationship operates through giving to religion. In the third section we show that giving by the 7 per cent of high givers increases the curvature while the giving by the 93 per cent of normal givers attenuates the curvature. In the fourth section we combine the previous two analyses by looking at the patterns of religious and non-religious giving for both normal and high givers. We conclude that income is not a reliable indicator of who is generous or selfish in regard to philanthropic giving.