Maturity period from time to time (amount doubles on maturity) :

IVP issued from 19.11.1986 to 01.09.1993................................5 years
                          02.09.1993 to 31.12.1998................................5 1/2 years
                          01.01.1999 to 15.07.1999................................6 years.

(Discontinued from 16.07.1999)