In: Finance
Today, you retire with $1,200,000 and you want to ensure that you can withdraw $1500 per week (52 weeks per year) and plan to earn a 4% rate of return. How many weeks will your original $1,200,000 last?
Amount Available = $1,200,000
P = Weekly withdrawl = $1,500
r = weekly interest rate = 4%/52 = 0.076923%
n = number of weeks
Number of weeks can be calculated using the below formula
PV = P * [1 - (1+r)^-n] / r
$1,200,000 = $1,500 * [1 - (1+0.076923%)^-n] / 0.076923%
$923.076923077 = $1,500 * [1 - (1.00076923)^-n]
1 - (1.00076923)^-n = 0.61538461538
(1.00076923)^-n = 0.38461538462
(1.00076923)^n = 2.60
n = log (2.60) / log(1.00076923)
n = 1242.64381867 weeks
Therefore, original amount will last for 1,243 weekd