Final answer:
The proportion of U.S. households that own stocks has decreased since the 2008 stock market collapse, due to the decline in the market value of financial assets. This decline in wealth impacted retirement and housing decisions.
Step-by-step explanation:
The proportion of U.S. households that own stocks has undergone changes since the stock market collapse of 2008. Prior to the collapse, the value of financial assets held by U.S. citizens was significant. However, as a result of the crisis, the market value of financial assets declined, causing a decrease in the proportion of households owning stocks. This decline in wealth affected many aspects of people's lives, including their retirement and housing decisions.