First-in first-out method, month-end weighted average method and moving weighted average method.

As a commodity, jewelry is always calculated by quantity × price. The difference is that the price of each purchase is 1, which is different and based on the original voucher (first-in, first-out method). 2. The same price is used according to the weighted average price calculated at the end of the month (weighted average method at the end of the month). 3. It is different, based on the moving weighted average price recalculated after each purchase.