Statement is a voucher for recording transaction information and expense details, and is used to clearly display transaction results and expense calculation. First of all, the statement should contain transaction information, such as transaction date, transaction object and transaction content, so that both parties can confirm the basic information of the transaction. Secondly, the expense details should list the specific content and amount of each expense, including the unit price, quantity and subtotal of goods or services. The details of expenses should be clear, so that both parties can check and understand the source and calculation method of expenses. Finally, the statement should summarize the total amount of all expenses so that both parties can understand the total cost of the transaction.