Taxes on products must be paid for each unit of a certain good/service that is produced or distributed. The tax may be a specific monetary amount for each good/service unit, or it may be calculated ad valorem as a specific percentage of a unit price or of a certain value. As a general rule, products that are subject to taxes must, regardless of the institutional unit paying them, be listed amongst the taxes on the products unless they are specifically included in another category.

Product subsidies are subsidies payable for a good/service unit that has been produced or imported. The subsidy may be a specific monetary amount for each good/service unit, or it may be calculated ad valorem as a specific percentage of a unit price or of a certain value. A subsidy may also be calculated as the difference between a given target price and the price that has actually been paid by the buyer.

Net Taxes on Products, or Taxes on Net Products of Subsidies, are defined as the difference between the Products less the Product Subsidies. In other words, they are defined as the difference between the total taxes payable as determined by each unit produced/distributed by a given good or service less subsidies, which are in turn also determined by the good/service unit that has been produced/imported.