Every valuation determined by the Municipal Property Tax Committee shall, subject to provisions of section 142, be final.

Period valuation: The annual valuation as finally determined by the Municipal Property Tax Committee:- (a) Shall have effect from the beginning of the year after the expiry of period of five years of the previous valuation or the beginning of the year in which it is made, whichever is later; (b) Shall, subject to the other provisions of the Chapter, remain in force in respect of each ward for a period of five years irrespective

of any alteration during such period in the number of boundaries of such ward; and

1. (c) May be revised on the expiry of each such period and the work relating to such revision shall be undertaken at least a year before such expiration: Provided that if for any reason to be recorded in writing the Municipality considers that it is not practicable to undertake the work relating to such revision before the expiry of one year. It shall seek prior approval of the Government stating reasons therefor, for its inability to undertake the revision.