Todd Zywicki does a nice job working out why two incomes mean less money than one income did 30 years ago:
Ms. Warren and Ms. Tyagi compare two middle-class families: an average family in the 1970s versus the 2000s (all dollar values are inflation-adjusted). The typical 1970s family is headed by a working father and a stay-at-home mother with two children. The father’s income is $38,700, out of which came $5,310 in mortgage payments, $5,140 a year on car expenses, $1,030 on health insurance, and income taxes “which claim 24% of [the father’s] income,” leaving $17,834, or about $1,500 per month in “discretionary income” for all other expenses, such as food, clothing, utilities and savings.
The typical 2000s family has two working parents and a higher income of $67,800, an increase of 75% over the 1970s family. But their expenses have also risen: The mortgage payment increases to $9,000, the additional car raises the family obligation to $8,000, and more expensive health insurance premiums cost $1,650. A new expense of full-time daycare so the mother can work is estimated at $9,670. Mother’s income bumps the family into a higher tax bracket, so that “the government takes 33% of the family’s money.” In the end, despite the dramatic increase in family income, the family is left with $17,045 in “discretionary income,” less than the earlier generation…. In fact, for the typical 1970s family, paying 24% of its income in taxes works out to be $9,288. And for the 2000s family, paying 33% of its income is $22,374.
Although income only rose 75%, and expenditures for the mortgage, car and health insurance rose by even less than that, the tax bill increased by $13,086 — a whopping 140% increase. The percentage of family income dedicated to health insurance, mortgage and automobiles actually declined between the two periods.
During this period, the figures used by Ms. Warren and Ms. Tyagi indicate that annual mortgage obligations increased by $3,690, automobile obligations by $2,860 and health insurance payments by $620 (a total increase of $7,170). Those increases are not trivial — but they are swamped by the increase in tax obligations. To put this in perspective, the increase in tax obligations is over three times as large as the increase in the mortgage payments and almost double the increase in the mortgage and automobile payments combined. Even the new expenditure on child care is about a quarter less than the increase in taxes.
I’m a bit skeptical of these computations, since at first glance this would seem to indicate that the wife’s car only cost sixty percent of the husband’s original car. Although, I suppose that the new leasing structures may account for that. One thing that is left out of Zywicki’s calculation, however, is the effect on the husband’s wage of all the other wives and single women who went to work in between 1970 and 2000; twice as many women work now as did in the 1950s. I don’t think it’s as important a factor as the taxes or even the second car, but it’s certainly played a major role in the decrease in average weekly wages since their 1973 peak.
Of course, it should surprise no one, least of all a libertarian with an econ degree, that the primary culprit is government and its overtaxation.