Returning to work for married women became financially much more worthwhile.
The introduction of independent taxation reversed a principle that had underpinned the tax system for almost two hundred years: that a married woman’s income was part of her husband’s income, and should be taxed as such. Since this reform, all individuals have been assessed for tax as separate persons. Prior to this change, married women often reported that the combined effect of a much higher marginal tax rate plus the costs of working (especially when childcare was counted by the couple entirely against her wages, rather than treated as a family expense) wiped out any income gain from working.