Section 168(3) in The Mumbai Municipal Corporation Act, 1888
(3)A new assessment book shall be prepared at the least once in every [five years] [These words were substituted for the words 'four years' by Maharashtra 27 of 2010, Section 8 (w.e.f. 26-8-2010).].[Special provisions concerning the Water and Sewerage taxes and charges] [This heading and sections 169 to 172 were substituted by Maharashtra 34 of 1973, Section 20.]