There are actually two sets of functions that can be used for loan calculation, the more general set will be discussed below. This set is for normal loan calculations where the term is in years, the interest rate is yearly, and the entire amount is to be paid off at the end of the loan period. For these calculations, all values are positive.
These calculate the amount of the loan, the monthly payments, the term in years, or the yearly percentage given the other 3., or the total interest or principle from the start to a given payment. Note that the interest rate calculation is done by trying values until one is found that matches the input values. There can be more than one answer possible. If it canít find an answer in a reasonable number of tries, it will return an error.
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LAmt |
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LAmt(mpay, yi, yrs) = amt |
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mpay: mo pay, yi: yr rate, yrs: yrs |
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Loan amount for mpay monthly |
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payments for yrs years |
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Amounts are all + for normal loans |
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yi is per year. If 8.5%, use 8.5 |
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LPay |
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LPay(amt, yi, yrs) = pay |
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amt: loan, yi: yr rate, yrs: yrs |
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Loan monthly payments for yrs years |
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Amounts are all + for normal loans |
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yi is per year. If 8.5%, use 8.5 |
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LYrs |
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LYrs(amt, mpay, yi) = yrs |
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amt: loan, mpay: mo pay, |
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yi: yr rate |
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Years to pay a loan |
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of amt with mpay monthly payments |
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and yearly int rate of yi |
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Amounts are all + for normal loans |
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yi is per year. If 8.5%, use 8.5 |
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LInt |
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LInt(amt, mpay, yrs) = yi |
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amt: loan, mpay: mo pay, |
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yrs: years |
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Yearly int rate |
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for loan of amt with mpay monthly |
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payments for yrs years |
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Amounts are all + for normal loans |
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This is yearly %, 8.5 = 8.5% |
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LTotI |
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LTotI(amt, yi, yrs, yr) |
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= total int paid from start to yr |
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amt: loan, yi: yr rate, yrs: years, |
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yr: year |
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Int paid to end of year yr |
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for loan of amt with yi yearly |
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interest for yrs years. Accurate to |
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1 month (yr can be fractional) |
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Amounts are all + for normal loans |
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LTotP |
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LTotP(amt, yi, yrs, yr) |
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= Total principle paid to yr |
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amt: loan, yi: yr rate, yrs: years, |
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yr: year |
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Princ paid to end of year yr |
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for loan of amt with yi yearly |
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interest for yrs years. Accurate to |
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1 month (yr can be fractional) |
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Amounts are all + for normal loans |