Final answer:
The term 'homogamy' explains the phenomenon where individuals with high incomes, such as professionals, marry each other, leading to higher combined household incomes and contributing to the widening gap of income inequality.
Step-by-step explanation:
The rise in female employment in the United States, especially in professional careers, when coupled with homogamy, has dramatically increased household incomes in the upper classes. The term 'homogamy' refers to the pattern of people marrying others who have similar socioeconomic status, such as doctors marrying doctors or executives marrying executives. This trend, which has become more common over recent decades, serves to concentrate wealth within these high-earning households, contributing to the growth of income inequality across the nation. Fundamentally, households with two high earners increase the proportion of high-earning households and widen the income gap between the richest and poorest populations of Americans.
In contrast to the past where a man with high earnings might marry a woman who earned less, and the woman might then leave the workforce to raise a family, today's patterns of marriage and employment have shifted. Mothers with high-powered careers are often returning to work while their children are quite young, maintaining dual-income households which further exacerbates income inequality. These changes in family structure have been identified as accounting for roughly half of the rise in income inequality across households in recent decades.