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Block 2 of our modal is the some as the aggregate
fertility
model of the Population CoP,nci I. This is used to estimate the
overall rates of contraceptive preva Lance that are needed to
achiove the TFR targots for tho years 191l6, 1991, 1996 and 2001.
These estimates ore used as inputs in Block 3.
Block 3 of our momdel is a modification of the ago-specific
version of the Population CounciL's modeL. We have attempted to
remove the deficiencies which we pointed out fn that modal. For
this purpose,
we have devised a complicated mathematicaL formula
containing, inter a lia,
the folLowing three purametars:­
(a Trnnd-regulato r R
Generally, a trend-based projection of the age-specific
contraceptive prevalence rates increases each base-year value in
the szane proportion. H.awver, a trend-regulator R which can be
assigned values within a certain range, positive as well as
negative, provides us with options und is one of the elements
enabling us to give a purposive re-orientation to the fami Ly
planning program.
The mathematical formula which we have used for
R applies varying rates of increase to the base year values - of.-­
age-specific CPR's, the positive values of R favoring higher
values of the CPR' s while the negative values of R represent a
shift from
an inverted U-shaped distribution of CPR's in the base
year towards a uniform distribution in the target year.
(b) Program re-allocation factor K
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We discovered through experimentation that
there
were
limits
to what the trend-regulator R could achieve. Therefore a second