IntDisc returns an interest discount factor from a future age to a current age, based on the assumption for interest. The discount can be based on the use of multiple interest rates that are in effect a various times or ages, such as for spot rates, forward rates, select & ultimate rates, etc. The discount is calculated from a future PaymentAge to the CommencementAge; and then discounted further from the CommencementAge to the CurrentAge 𝑥. The function ca also can return the interest rate 𝑖 and discount rate 𝑣 in effect at a given age.
·
If the interest rate is fixed,
this functions returns 
where 𝑡
= (future age – current age).
·
If the
interest rate is variable, this function returns 
, where 
.
Syntax
IntDisc (CurrentAge,
CommencementAge, PaymentAge, InterestRate, What)
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Parameter Name |
Description |
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CurrentAge |
Current age 𝑥.
May be provided as an integer, or as a fractional amount (e.g. years &
months). |
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CommencementAge |
Age at benefit commencement; blank = CurrentAge. |
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PaymentAge |
Age at payment -- not less than commencement age |
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InterestRate |
The interest rate(s) to discount future
payments to calculate the present value. May be a number, a percentage, a
text string, a named range, or reference to a range. ·
Rates
can be defined using these interest definitions. Note: A value that is greater than 25% (i.e. 0.25) will be divided by 100; e.g. if you enter 2.75 it will be treated as .0275 or 2.75%. |
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What |
What to return.
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