Time Value of Money (TVM)
Payment Mode Factor: S = 0 for End mode; 1 for Begin mode.
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0 = PV + | 1 + | ⋅ PMT ⋅ |
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Amortization
ΣINT = accumulated interest
ΣPRN = accumulated principal
i= periodic interest rate
BAL is initially PV rounded to the current display setting. PMT is initially PMT rounded to the current display setting.
i = | I ⁄YR |
For each payment amortized:
INT' = BAL × i (INT' is rounded to the current display setting; INT’ = 0 for period 0 in Begin mode.)
INT = INT' (with sign of PMT)
PRN = PMT + INT'
BALnew = BALold + PRN
ΣINTnew = ΣINTold + INT
ΣPRNnew = ΣPRNold + PRN
Interest Rate Conversions
EFF% = | ⎛⎛ | 1 | + | NOM% | ⎞ P ⁄ YR | ⎞ | ⋅ 100 | |
⎝⎝ | ⋅ P ⁄ YR⎠ | – 1 | ||||||
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II Appendix B: More About Calculations