87.  Charge of additional tax for failure to pay advance tax.-

(1)   Where an assessee who was required to pay tax under sub-section (1) of section 53,-

(a)    fails to pay any instalment; or

(b)    fails to pay any instalment on or before the specified date; or

(c)    fails to pay the full amount payable by him,

he shall, without prejudice to any other liability which he may incur under this Ordinance, be liable to pay additional tax at the rate of twenty-four per cent per annum on the amount not paid, and such additional tax shall be calculated from the date on which such amount was payable to the date on which it is paid or the thirtieth day of September of the financial year next following, whichever is the earlier.

(2)   Where, in respect of any year, any assessee fails to pay tax under sub-section (4) of section 53 or the tax so paid is less than eighty per cent of the tax chargeable for the relevant assessment year, he shall be liable to pay additional tax at the rate of twenty-four per cent per annum on the amount of tax so chargeable or the amount by which the tax paid by him falls short of the said eighty per cent, as the case may be; and such additional tax shall be calculated from the first day of April in that year to the date on which assessment is made or the thirtieth day of June of the financial year next following, whichever is the earlier.