Final answer:
The years 2009 to 2013 were tumultuous due to the Great Recession, leading over one hundred companies to drop off the Fortune 500 list as a result of a severe financial crisis and economic instability.
Step-by-step explanation:
Between 2009 and 2013, which were tumultuous years for the economy, over one hundred companies, including prominent ones like Bear Stearns, Chrysler, Circuit City, Merrill Lynch, RadioShack, and Tribune, vanished from the Fortune 500 list. This period marks the aftermath of the Great Recession, a time when the U.S. faced high unemployment, a decline in household wealth, stagnant wages, a severe drop in property values, and a stark decrease in the S&P 500 Index. The financial crisis led to a wave of bankruptcies and the exposure of fraudulent schemes like the one orchestrated by Bernard Madoff. Additionally, numerous corporate scandals and a lack of oversight in financial institutions like Lehman Brothers paved the way for this economic downturn, during which vital financial entities like Merrill Lynch had to sell themselves to survive.