Evidence on the Volunteer Labor Supply of Married Women

1. Introduction In this paper I investigate the volunteer labor supply of married women. There are dozens of studies that examine the labor supply of married women and a smaller number that investigate the supply of volunteer labor in general. As far as I know there are none that have focused on the supply of volunteer labor by married women. I analyze time diary data for the 1970s to consider one main question and three subsidiary questions. (i) What was the direct effect of economic variables (after-tax wage rate and other income) on married women's volunteering (both participation and hours)? (ii) Does the number of children in the family influence the volunteering of married women? To the extent that rising wages may induce smaller family size, is this an indirect channel that reduces volunteering (if one of the motivations for volunteering is to increase the quantity or quality of activities for one's own children)? The 1970s is an especially interesting time period to examine in the United States as that was the decade that saw the first large increases in married women's labor force participation rates. (iii) Are time and donations substitutes or complements for married women? (iv) Do the data support the Brown and Lankford (1992) modeling conjecture concerning a sequence of time allocation decisions as opposed to the Gronau model of household time allocation where such decisions are made simultaneously (Gronau 1986)? I find that (i) the volunteer labor supply for married women is positively sloped and inelastic with an estimated wage elasticity of +0.64. Rises in the net wage have a small negative effect on married women's participation in volunteer activities; a 25% rise in the net wage is associated with a 1% drop in the probability of volunteering. There is a small negative other income (from assets and husband's earnings) elasticity of volunteer labor supply, -0.09, so other sources of income mattered for married women's volunteering in the 1970s. The effect of other income on married women's volunteer participation is positive. (ii) Having more children increases the probability of volunteering but reduces the number of hours volunteered. (iii) Donations of time and money appear to be substitutes overall; the elasticity of married women's volunteer hours with respect to the tax price of giving is greater than two. The participation effect is again negative. (This result is tentative because the data are not based on tax return information and I lack good information on cash donations.) (iv) There is mixed support for the Brown and Lankford conjecture. The finding of a positive wage elasticity of volunteer labor supply is at odds with the opportunity cost of time interpretation of the wage, especially as the finding for other income is also negative, implying that volunteer hours are an inferior good. Substitution and income effects would, therefore, both be in a negative direction as the net wage rises. The results with the sequential specification are sensible and easily interpreted, but the key parameter estimate does not quite meet conventional standards of statistical significance. Increased hours of work decrease married women's participation and hours. An added test of the sequential model is less favorable. The wage findings suggest that rising wages for women caused a reduced incidence of volunteering among married women but, if anything, increased the hours of volunteering. One possible vehicle for this would be the entry of women into professional careers where volunteering is a normal part of the career. Another possible explanation is that married women with a loose attachment to volunteering stopped volunteering and those married women with greater attachment to volunteering increased their hours commitments to offset the participation effect. The link between children and volunteering is important as an indicator of how much selfinterest is involved in volunteering. For example, school volunteering may be a way of providing enhanced investment in one's own children where the benefit to others is a by-product. …