Regressive, proportional, and progressive tax systems can be found in the United States. High- and low-income earners are affected by these systems in different ways. Lower-income people are more affected by regressive taxation than the wealthy.
Low, middle and high-income earners are all affected by the same amount of the flat tax referred to as proportional tax. Taxes are levied at the same rate for everyone, regardless of their income. More wealthy taxpayers feel the pinch of a progressive tax than those at the bottom of the economic ladder.