(1)Where any Central Act enacts that income-tax shall be charged for any assessment year at any rate or rates, income-tax at that rate or those rates shall be charged for that year in accordance with, and [subject to the provisions (including provisions for the levy of additional income-tax) of, this Act] [ Substituted by Act 4 of 1988, Section 5, for " Subject to the provision of this Act" (w.e.f. 1.4.1989).] in respect of the total income of the previous year [* * *] [ Certain words omitted by Act 4 of 1988, Section 5 (w.e.f. 1.4.1989).] of every person:Provided that where by virtue of any provision of this Act income-tax is to be charged in respect of the income of a period other than the previous year, income-tax shall be charged accordingly.