A progressive tax imposes a higher percentage rate on taxpayers who have higher incomes.
On the pro side, a progressive tax system reduces the tax burden on the people who can least afford to pay. That leaves more money in the pockets of low-wage earners, who are likely to spend all of that money on essential goods and stimulate the economy in the process. A progressive tax system also tends to collect more taxes than flat taxes or regressive taxes, as the highest percentage of taxes is collected from the highest amounts of money.
我国《个人所得税》第三条第一段和第二段规定，综合所得适用百分之三至百分之四十五的超额累进税率，经营所得适用百分之五至百分之三十五的超额累进税率。（超额累进税率（excess progressive tax rate）是累进税率的一种，以征税对象的超额部分为基础计征税款，征税对象数额超过某一等级时，仅就超过部分按高一级税率计算征税。）
A proportional tax is an income tax system that levies the same percentage tax to everyone regardless of income. A proportional tax is the same for low, middle, and high-income taxpayers. Proportional taxes are sometimes referred to as flat taxes.
A regressive tax is a tax applied uniformly, taking a larger percentage of income from low-income earners than from high-income earners. It is in opposition to a progressive tax, which takes a larger percentage from high-income earners.
Low-income individuals pay a higher amount of taxes compared to high-income earners under a regressive tax system. That's because the government assesses tax as a percentage of the value of the asset that a taxpayer purchases or owns. This type of tax has no correlation with an individual's earnings or income level.
Regressive taxes include property taxes, sales taxes on goods, and excise taxes on consumables, such as gasoline or airfare. Excise taxes are fixed and they're included in the price of the product or service.