How to calculate the stamp duty on sales contracts?

I answered a similar question once. The Provisional Regulations on Stamp Duty stipulates that tax payable vouchers should be stamped when the account books are set up or received, and the basis for collection is the contract amount. In order to further strengthen the management of stamp duty collection, the provinces have formulated the Interim Measures for the Verification and Collection of Stamp Duty. For taxpayers of stamp duty on purchase and sale contracts, the approved collection ratio shall be determined according to the following standards: \x0d\ 1. For units and individuals engaged in the purchase and sale of industrial goods, the stamp duty applied for in the procurement process shall be taxed according to the proportion of 50%- 100% of the purchase amount. The stamp duty applicable to its sales links shall be levied at the rate of 60%- 100% of the sales revenue. \x0d\ 2。 For commodity circulation units and individuals engaged in the purchase and sale of commodities, the stamp duty applied for in the procurement process shall be approved as the tax basis according to the proportion of 60%- 100% of the purchase amount; The stamp duty applicable to its sales links shall be levied at the rate of 20%- 100% of the sales revenue. \x0d\ 3。 For units and individuals engaged in real estate development, the stamp duty applied for in the procurement process shall be levied according to the proportion of 70%- 100% of the purchase amount; Stamp duty applicable to its sales links shall be levied according to the proportion of 100% of sales revenue. \x0d\ Taxable amount = purchase and sale amount * approved collection rate *0.03%.