# Math Help - Future Value @ incr. rate

1. ## Future Value @ incr. rate

Code:
YR    RATE      INTEREST      BALANCE
0                             1000.00
1    .03         30.00        1030.00
2    .033        33.99        1063.99
3    .0363       38.62        1102.61
4    .03993      44.03        1146.64
Above is an example of future value of an amount at an incresing rate:
\$1000.00 at rate 3% 1st year, then the rate increasing by .10 each year.
As example, year2 rate = .03 * 1.10 = .033

What is the formula to calculate the future value in such circumstances?

2. ## Re: Future Value @ incr. rate

If an approximation will do, try the continuous version - then you can throw some integration at it.

3. ## Re: Future Value @ incr. rate

Thanks. But to be exact, only a "looper" will do it, I guess:

a=1000:r=.03:i=.10:n=4

FOR y = 1 TO n

k = a * r [this period's interest]

a = a + k [this period's resulting principle]

PRINT y,k,a

r = r * i [update rate]

NEXT y