Bond calculations
In its bond calculations, this calculator conforms to rules set up by the book titled Standard Securities Calculation Methods, by Jan Mayle, Securities Industry Association, 1993.
Bond calculation is based on the following rules:
1.Whenever the redemption date happens to be the last day of a month, coupons are also paid on the last days of months. For example, if coupon payments are
2.If coupons are to be paid twice a year and the redemption date is set to August 29, 30, or 31, coupon payments for February occur on the 28th (29th for leap years).
3.The “Odd Coupon” is not supported.
4.All data stored or calculated for bonds are assumed to be posi- tive values. Negative values in any of the variables used by bond calculations will cause errors.
The formulas used for bond calculations are shown using the follow- ing variable definitions:
TD: Total number of days in the coupon period that begins with the coupon date previous to the settlement date and ends with the first coupon date after the settlement date. (On the
PD: The number of days preceding the settlement date in the cou- pon period described above. (see “Day and date calculations”)
FD: The number of days following the settlement date in the coupon period described above (in TD).
FD = TD – PD
NP: The number of whole coupon periods between the settlement date and the redemption date (rounded up to the next highest whole number, if necessary).
For one coupon period or less until redemption of bond: 
For more than one coupon period until redemption:
where CPN = COUPON(PMT), RDV = REDEMPT(FV), N = CPN/Y(N), YIELD = YIELD(I/Y), PRICE = PRICE(PV).
Yield is obtained as YIELD, which satises the above equations.
Error
CPN < 0 or RDV < 0 or PRICE < 0 or
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