10- The previous law included this provision, but it was not carried out in practice. 8. Third-party responsibility: Those who, under the law, have an obligation to withhold taxes on a particular transaction are jointly responsible for any taxes omitted, Similarly, those who acquire commercial, industrial, agricultural, live-stock raising or fishing businesses, credits or concessions which are the sources of taxed income, assume responsibility for the payment of any taxes omitted by the transferror (the previous law contained similar provis ions). 9. Statute of limitations: The Treasury Department continues to have the power to review tax returns for a period of five years and, if taxes have been omitted, can assess additional taxes, which are payable with surcharges of 2% monthly, computed from the date on which the payment of such taxes should have been made, plus the applicable fines. The surcharges cannot exceed 48% of the omitted tax. The new law also includes the previous provision to the effect that after five years have elapsed, "which cannot be interrupted", action by the tax authorities is barred by the statute of limitations. Tax-payers must retain all records and documents relating to their tax re- turns for such period. II. TAX ON COMBINED INCOME OF ENTERPRISES This tax is applicable to, those taxpayers who were subject to Schedules I (commercial activities), II (industrial activities) and III (agricultural, livestock raising or fishing activities) under the previous law. 10. Taxable income: The income subject to tax for companies, branches of foreign companies or individual enterprises is the difference between total gross income and the deduction of the costs and expenses related to such income, with certain limitations and requirements which are discussed subsequently. 11. Tax rates: The tax applicable to the combined taxable income of business enterprises is based on a new progressive tax table, which ranges from a 5% tax on combined annual income of US$160 up to a 42% tax on annual income in excess of US$80,000. The regular income tax table of the previous law (excluding the former excess profits tax), applicable to Commercial or industrial activities, ranged from 5% on annual income of US$160 up to 39% on annual income in excess of US$160,000.