Swaps interest calculation date

Although for the purposes of explaining swap structures both parties are said to pay and receive interest payments, in practice only the net difference between both payments changes hands at the end of each interest period. This makes administration easier and reduces the number of cash flows for each swap. The final payment date falls on the maturity date of the swap. Interest is calculated using equation (7.1). 

A forward-start swap s effective date is a considerable period—say, six months—after the trade date, rather than the usual one or two days. A forward start is used when one counterparty, perhaps foreseeing a rise in interest rates, wants to fix the cost of a future hedge or a borrowing now. The swap rate is calculated in the same way as for a vanilla swap. 

To derive the swap term structure, observed market interest rates combined with interpolation techniques are used also, dates are constructed using the applicable business-day convention. Swaps are frequently con-strncted nsing the modified following bnsiness-day convention, where the cash flow occurs on the next business day unless that day falls in a different month. In that case, the cash flow occurs on the immediately preceding business day to keep payment dates in the same month. The swap curve yield calculation convention frequently differs by currency. Exhibit 20.2 lists the different payment frequencies, compounding frequencies, and day count conventions, as applicable to each currency-specific interest rate type. 

The final component of the default swap is the accrued premium that may be payable by the buyer to the seller. If a default occurs somewhere in between two premium payment dates, which is likely considering there are only four payment dates a year on a quarterly default swap, then it is standard market practice for the buyer of protection to pay the accrued premium from the most recent premium payment date to and including the date of default. The value of this accrued on default is calculated in a similar manner to the value of the default protection above. However, instead of receiving 1 - R upon a default, the buyer will be paying a certain amount of accrued interest. 

An interest rate swap is an agreement between two counterparties to make periodic interest payments to one another during the life of the swap. These payments take place on a predetermined set of dates and are based on a notional principal amount. The principal is notional because it is never physically exchanged—hence the off-balance-sheet status of the transaction—but serves merely as a basis for calculating the interest payments. 

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