The IW evaluation effectively compares salaries to the median wage across Germany within different groups to define; low, lower middle, middle, upper middle and wealthy income levels.
A lower middle class wage would be between €1,450 and €1,940, with a middle class wage extending up to €3,630.
Up to €2,900, one is assigned to the lower middle class, and with up to €5,440 per month to the middle class.
Earning up to €9,070 puts one in the upper middle class, and earning more than that makes you rich.
Above that and up to €4,060, marks the lower middle class, and then above that and up to €7,620 marks the middle class.