Perpetuity: Difference between revisions

From ACT Wiki
Jump to navigationJump to search
imported>Doug Williamson
(Slight rewording to make description clearer)
imported>Doug Williamson
(Remove excessive referencing of annuities.)
Line 1: Line 1:
1.
===== Fixed perpetuities =====


A perpetuity is similar to an annuity except that the fixed periodic cash flow starting one period into the future then carries on for ever (‘in perpetuity’) rather than stopping at a future point.  
A fixed perpetuity is a periodic cash flow starting one period in the future, then carrying on for ever - ‘in perpetuity’.
Each cash flow is an equal fixed amount.


The present value of a fixed perpetuity is calculated - assuming a constant periodic cost of capital (r) for all periods from now to infinity - as:
The present value of a fixed perpetuity is calculated - assuming a constant periodic cost of capital (r) for all periods from now to infinity - as:
Line 8: Line 9:




2.
where:


For a growing perpetuity the present value formula is modified to take account of the constant periodic growth rate starting from one period into the future to infinity as:
A<sub>1</sub> = Time 1 cash flow


Present Value = A<sub>1</sub> x 1/[r-g]
r = periodic cost of capital
 
 
===== Growing perpetuities =====
 
For a growing perpetuity, the present value formula is modified to take account of the constant periodic growth rate from one period in the future to infinity, as follows:
 
Present Value = A<sub>1</sub> x 1 / (r - g)


where g = the periodic rate of growth of the cash flow.
where g = the periodic rate of growth of the cash flow.


The growing perpetuity concept is applied by the Dividend growth model for share valuation.
 
The growing perpetuity concept is applied in many contexts.
 
For example, the Dividend growth model for share valuation.





Revision as of 10:03, 31 May 2015

Fixed perpetuities

A fixed perpetuity is a periodic cash flow starting one period in the future, then carrying on for ever - ‘in perpetuity’. Each cash flow is an equal fixed amount.

The present value of a fixed perpetuity is calculated - assuming a constant periodic cost of capital (r) for all periods from now to infinity - as:

Present Value = A1 x 1/r


where:

A1 = Time 1 cash flow

r = periodic cost of capital


Growing perpetuities

For a growing perpetuity, the present value formula is modified to take account of the constant periodic growth rate from one period in the future to infinity, as follows:

Present Value = A1 x 1 / (r - g)

where g = the periodic rate of growth of the cash flow.


The growing perpetuity concept is applied in many contexts.

For example, the Dividend growth model for share valuation.


See also