# How is the discount calculated? ### How is the discount calculated?

the calculation of one discount se made on the same principle as that used to calculate the tax; it comes back to a calculation of “so many percent”. However, rather than adding a certain amount to the base price, as in the case of taxes, the value of the purchase must be reduced by a certain amount.

### How to calculate purchasing power?

A priori, the equation is simple: purchasing power is the quantity of goods and services that we can consume with the money we have. It therefore depends on two factors: the price level, which also changes over time (inflation or deflation).

### How to calculate a discount?

Calculation of a rebate The calculation of a rebate is done according to the same principle as that used to calculate the tax; it amounts to a calculation of “so many percent”. However, rather than adding a certain amount to the base price, as in the case of taxes, the value of the purchase must be reduced by a certain amount.

### How to calculate the amount of an invoice?

The amount of the product concerned is directly deducted from the initial invoice. The invoice is recorded as a net amount (i.e. minus the discount). In case of omission on the departure invoice, the discount must be the subject of a credit note.

### How is purchasing power calculated?

How is purchasing power calculated? While the government had promised an increase in purchasing power, the increase in the CSG or tobacco give an impression contrary to public opinion. For the government, purchasing power will increase in 2018 under the effect of reductions in employee contributions and taxes.