America's shrinking middle class is killing the economy

The middle-income class is hollowing out, and it's hurting US economic growth.
Only about a quarter of a percent of US households have climbed up the ladder from the middle class into the upper-income bracket since 2000, according to the latest review by the IMF. Meanwhile, more than 3% of middle-income households have moved into the low-income bracket.That's a flip from the trend between 1970 and 2000, where middle-income households were more likely to mo