If the income obtained by foreigners is in foreign currency, it shall be converted into RMB according to the foreign exchange quotation (buying price) published by the People's Bank of China on the last 1 day of last month when the tax payment certificate is filled in, and the taxable income shall be calculated. According to the provisions of the tax law, foreign currency income that has been paid in advance on a monthly basis or every time will not be converted if it is settled after the end of the year; The supplementary portion of the taxable income shall be converted into RMB according to the foreign exchange quotation (buying price) published by the People's Bank of China on the last 1 day of the previous tax year to calculate the taxable income.