From the summary:
A middle-class standard of living requires that families have adequate financial security to meet current obligations, invest in the future, and access opportunities. The most recent findings from the Middle Class Security Index show that between 2000 and 2006–even before the most recent economic downturn–the economic well-being of middle-class families slipped noticeably.
Between 2000 and 2006 an estimated 4 million middle-class families lost their financial security, bringing the total number of middle-income families on shaky ground to 23 million.
These worrisome changes in the overall financial health of the middle class were driven
by a decline in assets, rising housing costs, and a growing lack of health insurance.
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