# Future Value @ incr. rate

• Apr 11th 2012, 04:22 PM
Wilmer
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?
• Apr 12th 2012, 09:50 AM
SpringFan25
Re: Future Value @ incr. rate
If an approximation will do, try the continuous version - then you can throw some integration at it.
• Apr 12th 2012, 11:43 AM
Wilmer
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