The charts on this page (from the Pew Research Center) reflect the middle class in the United States and in various European nations. The chart above shows the percentage of citizens that are in the middle class. Note that the United States trails all of the other nations in size of the middle class, and leads all those nations in the size of lower income people.
This is due to the "trickle-down" economic policy instituted in the United States. This policy favors the rich, and has contributed to a shrinking middle class. And it's a policy that none of the European nations adhere to.
The chart below shows the range of incomes in each country considered to be a middle class income. They define middle class as having an income that is between two-thirds and double the median income of the country. In the United States, that would be an income between $21,257 and $105,881.
