The Two-Currency Household
Two partners, A and B, share a household. A earns 90,000 units a year and works 55 hours a week; B earns 30,000 and works 25 hours a week, and does about 30 hours a week of unpaid housework and childcare. They have one child (age 4) and a mortgage of 200,000. They keep separate accounts and split shared bills 50/50.
After three years, B says the arrangement is unfair: B's paid income is low because B reduced hours to cover childcare, but B still pays half the bills and does most of the housework. A replies: 'We split bills equally, so it's fair; and I earn more because I work more hours.' A also points out that A's student loan (25,000) is being repaid from A's income.
A spreadsheet shows that if B returned to full-time work, the household would pay 18,000 a year more in childcare and lose some benefits, netting only 4,000 extra.
1. Analyse the household as an economic unit. Why does the 50/50 split of monetary bills not produce a fair division of the household's total product?
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The household produces a total product made of two components: market income (120,000) and non-market household labour (B's ~30 hours of care and housework, which would cost a large sum if purchased). The 50/50 split of bills counts only the first component and ignores the second entirely.
Consequences:
- B's contribution is invisible in the accounting: it is real, valuable, and unpaid, so it never enters the 'who pays what' calculation.
- B's reduced market hours are not a free choice; they are the result of the household's division of labour, which was itself shaped by the childcare need and by the pay gap. A's higher earnings are partly enabled by B's unpaid work - A can work 55 hours because B covers the home.
- The 50/50 rule therefore applies an equal rule to unequal positions, which reproduces inequality rather than correcting it.
A's argument ('I work more hours, so I earn more, so equal bills are fair') treats market hours as the only input. Correcting the accounting means recognising household labour as an input to the household's total income, and allocating both burdens and consumption with that in view - not merely splitting the visible bills.
2. Using the spreadsheet figure (returning to full-time work nets only 4,000 extra), explain why B's 'choice' to work part-time is constrained. What does this imply about the claim that the arrangement is voluntary?
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The figure shows that B's move to full-time work would raise gross earnings substantially but net only about 4,000 a year, because 18,000 goes to purchased childcare and some benefits are lost. That is a very low return for a large increase in hours and stress.
This is a constrained choice: the option 'work full-time' exists formally but is heavily penalised by the structure of childcare costs and benefit withdrawal. Economists describe the result as a participation trap - the effective marginal reward for working more is small or negative once costs are counted. B is not choosing part-time work from preference alone; B is choosing the least-bad option given the constraint.
Implication for 'it's voluntary': voluntariness requires (a) acceptable alternatives and (b) information and freedom from pressure. Here the alternative is poor by construction (net 4,000 for a large increase in hours), and the household division of labour is shaped by that. So the arrangement is formally voluntary but substantively constrained. That matters ethically: a distribution produced under a constraint cannot be defended simply by saying 'each chose it'. It also matters practically - the fix may be external (childcare provision, benefit design) as much as internal (reallocating housework between A and B).
3. Propose a concrete reallocation rule for the household and justify it. How should A's student loan be treated, and what should happen to the 4,000 net gain if B returns to work?
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Principle. Allocate by capacity to contribute, measured on the household's combined resources including the value of unpaid work, not by separate incomes and not by a 50/50 bill split.
Rule.
- Pool the household's necessary costs (housing, food, childcare, utilities) and pay them from a joint account funded proportionally to each partner's total contribution - market income plus an imputed value for household labour hours. On the given numbers, B's 30 hours of care count as a contribution, so B's share of the joint costs falls well below 50%.
- Each partner keeps a personal allowance of equal size from their own income, so neither is financially dependent for discretionary spending.
- Revisit the split when hours or earnings change.
The student loan. It is A's individual obligation, incurred before or independently of the household's shared consumption. It should be repaid from A's personal share, not from joint funds - unless the household explicitly agrees that the qualification benefits both (which is arguable if A's higher earnings support the household). The default should be individual, with an explicit, recorded exception.
The 4,000. If B returns to work, the gain is small and the extra burden (childcare logistics, household labour shortage) is real. The rule should be: the gain stays with B as personal income for a defined period, and A takes on a larger share of housework to make the extra hours feasible. Otherwise B bears the cost of the change and A captures the benefit - which is the current unfairness in a new form.
The general justification: fairness in a household is not equal bills; it is equal treatment of unequal contributions, including the ones that never appear on a bank statement.