Final answer:
The best description of the faster income growth for older people compared to younger people since the 1980s is the 'Income Inequality Shift'. This is due to changes in household dynamics and wage distribution within the U.S. economy.
Step-by-step explanation:
The phenomenon where the income of older people in the United States has grown faster than the income of younger people is best described by option (d) Income Inequality Shift. Since the 1980s, a trend toward greater income inequality has been observed across many countries, with a pronounced effect in the U.S. economy. The rise in inequality can be attributed to factors including the changing shape of American households and a shift in wage distribution, often referred to as winner take all labor markets. In the context of the elderly, while there has been an improvement in poverty rates over the decades, events like the 2008 recession have had a noticeable impact on the financial futures of older individuals. As the baby boomer generation enters retirement, the dynamics of social institutions, labor markets, and economic stability are undergoing significant change.