THE IRA (TI-92)
This program calculates a retirement savings account balance given a annual deposit, p, an annual interest rate, i, and the number of years until retirement, t.
- :ira()
- :Prgm
- :{0}=>l1
- :Disp "ANNUAL DEPOSIT"
- :Input p
- :Disp "TIME UNTIL RETIREMENT"
- :Input t
- :Disp "INTEREST RATE"
- :Input i
- :i/100=>i
- :For(j,1,t,1)
- :p*(1+i)^j=>l1(j)[1]
- :EndFor
- :Disp sum(l1[1])
- :EndPrgm
Discussion:
"Compounding is mankind's greatest invention because it allows for the reliable, systematic accumulation of wealth," said Albert Einstein.
What is an IRA?
What kind of return on investments can we expect?
What is inflation?
What is OASDI/Social Security?
Is there a closed form formula for the total rather than "sum(l1[1])"?
How does one achieve a higher rate of return?
What is the rule of 72, 70, 69?
Assignments:
How much do you have to save annually at X% interest in order to have Y dollars when you retire? ...and when you adjust for Z% inflation?
How much do you have to save every year at 10% to have a $1,000,000 when you retire. Adjust for 5% inflation.
What is a 401k? How does it work?