The tax rate refers to the ratio between the taxable amount of the taxpayer and the amount of the taxable object, and is the legal measure for calculating the taxable amount. The tax rate is directly related to the amount of national fiscal revenue and the weight of taxpayers' burden, reflecting the depth of national taxation and is the core element of the tax system.

Invoice refers to the business vouchers issued and collected by all units and individuals in buying and selling goods, providing or receiving services and engaging in other business activities. It is the original basis of accounting, and it is also an important basis for law enforcement inspection by audit institutions and tax authorities. Receipt is the proof of receipt and payment, and invoice can only prove that the business has happened, but can't prove whether the money has been received or paid.