20- 31. Tax on the gross revenues _of foreigners:_ The following types of income received by foreigners continue to be taxed on the gross amount at the same rates as under the previous law, except for those set forth in paragraphs "c" and "d", to which the new progressive rates are applied); a) Technical assistance -- 20%. b) Interest paid to foreign banks not domiciled in the country, or to other foreign enterprises when the funds obtained are used for purposes which, in the judgment of the Treasury Department, are of general interest -- 10%, c) Royalties and other payments for the use of invention patents, trade marks and brand names -- the new progressive rates of Exhibit A. d) Interest and other yields of capital -- the new progressive rates of Exhibit B. e) Reinsurance premiums paid by Mexican enterprises -- 4%. Entities making payments of such types of income must with-hold the related tax, for which they are jointly responsible. 32. Revaluation of fixed assets _or capital:_ The new law prohibits the revaluation of fixed assets or capital for tax purposes, but it establishes that if revaluations have been previously made with the express authorization of the Treasury Department and with payment of the related tax in accordance with the provisions of the previous law, such revaluations will continue to have tax effect. III, TAX ON INCOME OF INDIVIDUALS The new income tax law taxes the income of individuals by classifying the income in three groups: A- Tax on income from personal services. This group com-prises those individuals who were taxed under Schedules IV and V under the previous law. B. Tax on income from capital investments. This group com- prises all income obtained by individuals which, under the previous law, was taxed under Schedules VI, VII, VIII, and IX. C. Tax on combined income of individuals. This group in- cludes the income of individuals taxed under one or