43 government of all current year collections of internal revenue taxes, within the area of autonomy shall, for a period of five (5) years be allotted for the Regional Government in the Annual Appropriations Act. The Bureau of Internal Revenue (BIR) or the duly authorized treasurer of the city or municipality concerned, as the case may be, shall continue to collect such taxes and remit the share to the Regional Autonomous Government and the central government or national government through duly accredited depository bank within thirty (30) days from the end of each quarter of the current year; Fifty percent (50%) of the share of the central government or national government of the yearly incremental revenue from tax collections under Sections 106 (value-added tax on sales of goods or properties), 108 (value-added tax on sale of services and use or lease of properties) and 116 (tax on persons exempt from value-added tax) of the National Internal Revenue Code (NIRC) shall be shared by the Regional Government and the local government units within the area of autonomy as follows: (a) twenty percent (20%) shall accrue to the city or municipality where such taxes are collected; and (b) eighty percent (80%) shall accrue to the Regional Government. In all cases, the Regional Government shall remit to the local government units their respective shares within sixty (60) days from the end of each quarter of the current taxable year. The provinces, cities, municipalities, and barangays within the area of autonomy shall continue to receive their respective shares in the Internal Revenue Allotment (IRA), as provided for in Section 284 of Republic Act No. 7160, the Local Government Code of 1991. The five-year (5) period herein abovementioned may be extended upon mutual agreement of the central government or national government and the Regional Government.