Since the value of the bond portfolio is merely the present value of future cash flows, using the concepts of duration defined below, such approximations can be done quickly using nothing more than a handheld calculator. Using convexity together with duration gives a better. Introduction the basic bond valuation formula is traditionally presented as a straight forward discounted cash flow application. Longterm bonds have greater interest rate risk than short term bonds. Sep 06, 2019 the modified duration alone underestimates the gain to be 9. Duration and convexity 443 that duration is a measure of interest rate risk is demonstrated as follows. For a bond of face value usd1,000 with a semiannual coupon of 8. The standard approximation using the duration and convexity described above does not include the passage of time.
A bonds convexity refers to the sensitivity of the bonds modified duration to changes in yield. This paper provides a theoretical and practical overview of the concepts, largely missing in the existing. Convexity indicates that as yield increases, the price of a bond declines at a declining rate. Jul 22, 2011 this video illustrates how duration can be used to approximate the change in bond price given a change in interest rates. The relationship between required yield and price is generally stated as bond prices and. However, also implicit in the convexity measure is the assumption of parallel shifts in yields and, therefore, the durationconvexity. Bond duration and convexity spreadsheet the bond duration worksheet allows you to calculate the duration of a bond quickly and easily. Common misunderstandings concerning duration and convexity.
Bond portfolio duration, cash flow dispersion and convexity article pdf available in applied economics letters 1717. For a standard bond the macaulay duration will be between 0 and the maturity of the bond. Some evidence suggests that the yield curve is more curved when volatility is higher and convexity is worth more. Understanding duration and convexity of fixed income. One method of measuring interest rate risk due to changes in market interest rates is by the full valuation approach, which simply calculates what bond prices will be if the interest rate changed by specific amounts.
Exhibit 3 shows that over the last 20 years, the aggregate indexs durationsquared term has always been. Duration measures the bonds sensitivity to interest rate changes. Bond duration and convexity introduction continued economics of capital markets version 1. Pdf immunization is a wellknown fixedincome strategy to lock in a target rate of return over a known investment horizon. Convexity is always lurking at the scene of the crime. Using duration and convexity to approximate change in. For example, if a bond has a duration of 5 years, and interest rates increase by 1%, the bonds price will decline by approximately 5%. Conversely, if a bond has a duration of 5 years and interest rates fall by 1%, the bond s price will increase by approximately 5%. The modified duration alone underestimates the gain to be 9. Modified duration, on the other hand, is a mathematical derivative rate of change of price and measures the percentage rate of change of price with respect to yield. However, also implicit in the convexity measure is the assumption of parallel shifts in yields and, therefore, the duration convexity. Fixed income portfolio management interest rate sensitivity. Macauley duration modified duration effective duration percentage change in price for a 1% increase in the yield to maturity problem 2 consider a bond that has a coupon rate of 7.
Understanding duration and convexity of fixed income securities vinod kothari notation y. Financial expert frank fabozzi walks you through every aspect of bond risk measures from the price volatility characteristics of optionfree bonds and bonds with embedded options to the proper method for calculating duration and convexity. For zeroes, duration is roughly equal to maturity, convexity is roughly equal to maturity squared. Pdf bond portfolio duration, cash flow dispersion and. Estimate the percentage price change of a bond for a specified change in yield, given the bonds approximate duration and convexity.
Macaulay duration of coupon bond 1storder approximation of bond price change 1storder approximation of dv01 convexity convexity of zerocoupon bond convexity of coupon bond 1storder approximation of duration change 2ndorder approximation of bond price change duration of portfolio duration neutral. The approximate change using both dollar duration and convexity is. Considering duration and convexity duration assumes a linear relationship between bond prices and changes in interest rates. The present value equation for an annual coupon bond is given by. Krzysztof ostaszewski, and hansjoachim zwiesler abstract the concepts of duration, convexity, and immunization are fundamental tools of assetliability management. Think of bond prices, or bond portfolio values, as functions of interest. Price change of a bond duration convexity cfa level. Pdf enhancement of the bond durationconvexity approximation.
Pdf hedging bond positions under the assumption of a parallel shift of the interest rate curve is. Modified duration and convexity taken together provide the best approximation of the sensitivity of bond prices to changes in interest rates. Convexity builds on the concept of duration by measuring the sensitivity of the duration of a bond as yields change. Bond convexity is one of the most basic and widely used. Chapter 11 duration, convexity and immunization section 11.
Bond duration is a way of measuring how much bond prices are likely to change if and when interest rates move. Convexity formula how to calculate convexity of a bond. However, bond investors have been customarily used to using duration and convexity, as discussed below and quick and handy tools for understanding the sensitivity of bond prices to yields. Bond duration calculator macaulay duration and modified macaulay duration. We provide tables if changing slope as yield changes illustrates. Using duration and convexity to approximate change in present value robert alps october 28, 2016. Since the value of the bond portfolio is merely the present value of future cash flows, using the concepts of duration defined below, such. Convexity 7 the convexity correction is always positive suppose the 20year rate fell 100 bp 5. The duration of a bond varies with the passage of time and yield changes. Convexity relates to the interaction between a bonds price and its yield as it experiences changes in interest rates. Pdf hedging bond positions under the assumption of a parallel shift of the interest rate curve is wellknown and used for a long date in finance.
This video illustrates how duration can be used to approximate the change in bond price given a change in interest rates. Convexity is a better measure of interest rate risk, concerning bond duration. Coupon payment frequency pf this field indicates whether the coupon is paid annually or semiannually. A primer on duration, convexity, and immunization leslaw gajek. Bond duration calculator macaulay duration and modified. Enter the coupon, yield to maturity, maturity and par in order to calculate the coupon bonds macaulay duration, modified macaulay duration and convexity. On one hand, in the case of a callable bond, a change in interest rates may trigger the calling of the bond, thus stopping the flow of. A bond has positive convexity if the yield and the duration of the bond increase or decrease together, i. Price change of a bond duration convexity cfa level 1. Pdf bond portfolio duration, cash flow dispersion and convexity. T 1 c yt f t, where y ytm when yields change, bond prices will change. They also enter into measures for interest rate risk, as shown in this paper.
Bond calculator macaulay duration, modified macaulay duration, convexity coupon bond calculate bond macaulay duration, modified macaulay duration, convexity. The bonds cash flows consist of coupons paid periodically and principal repaid at maturity. Duration measures the bond s sensitivity to interest rate changes. Using duration and convexity to approximate change in present. Revisiting the bond durationconvexity approximation. In general, the higher the duration, the more sensitive the bond price is to the change in interest rates. In particular, these measures can be used for approximation of a bonds sensitivity to changes in the term structure of interest rates. Determine how much money you would accumulate by investing a given amount of money at a fixed annual rate of return at recurring intervals. Callable bond is one which can be prepaid by the bond issuer prior to its maturity. If interest rates applicable for discounting fall rise, both va and vl will increase decrease. Duration, modified duration, and convexity reflect the bonds exposition to interest rate risk.
As the yield on a bond changes so too does its duration, a bonds convexity measures the sensitivity of a bonds duration to changes in yield. Application of the concepts of duration and convexity to portfolio will be clari. The sensitivity of the percentage bond price change to changes in. Duration is an imperfect way of measuring a bonds price change, as it indicates that this change is linear in nature when in fact it exhibits a sloped or convex shape. Pdf duration and convexity of bonds slobodan cerovic. The coupon rate is typically stated in an annual percentage.
Just as with dollar duration, the dollar convexity of the portfolio is the sum of the dollar convexities of the component zeroes. Also, the duration of the bond when its yielding 12. Duration, modified duration, and convexity reflect the bonds exposition to interest rate risk and are used as tools for risk management purposes. An explanation of the concept of convexity and how it is used in con unction with. Yield duration and convexity relationships yield duration the relationship between yield duration and maturity yield convexity bloomberg yield duratio. Conversely, if a bond has a duration of 5 years and interest rates fall by 1%, the bonds price will increase by approximately 5%.
It is equal to the maturity if and only if the bond is a zerocoupon bond. Fixed income portfolio management interest rate sensitivity, duration, and convexity passive bond portfolio management active bond portfolio management interest rate swaps 1 interest rate sensitivity, duration, and convexity tbond price. Duration is an imperfect way of measuring a bonds price change, as it indicates that this change is linear in nature when in. Nov, 2019 duration and convexity are two tools used to manage the risk exposure of fixedincome investments. Annuity factors simplify valuation of level cash flows, such as the coupon payments of bonds.
As the expiration date approaches, duration declines. Duration and convexity are two tools used to manage the risk exposure of fixedincome investments. Convexity of a bond can be defined as a measurement of the curvature in relation to changes in interest rates which shall affect the changes in the price of a bond and further it does so by measuring the duration changes, as the market interest rates fluctuate. Although procedures and formulas exist to calculate duration and convexity, these statistics can be approximated using basic bondpricing techniques and a financial calculator. Enter the coupon, yield to maturity, maturity and par in order to calculate the coupon bonds. Duration, convexity and other bond risk measures offers the most comprehensive coverage of bond risk measures available. In finance, bond convexity is a measure of the nonlinear relationship of bond prices to changes in interest rates, the second derivative of the price of the bond with respect to interest rates duration is the first derivative. This typical is for a bond which does not have a call option or a prepayment option. The use of convexity matching, in addition to duration matching, is an attempt to explain the price sensitivity in a better fashion. If an investor is given a choice of two 10year bonds to choose from, one with a 10 percent coupon rate and the other with a 5 percent coupon rate. Bond duration and convexity introduction continued bond duration and convexity introduction continued economics of capital markets version 1.
Bond convexity decreases increases as bond yield increases decreasesthis property holds for all optionfree bonds. A few applications of duration in risk management will also be presented. Duration and convexity, with illustrations and formulas. Given the convexity measure, the convexity adjustment to the duration estimate can be computed. Understanding bond duration can help investors determine how bonds fit in to a broader investment portfolio. In terms of callability feature, bonds may be callable or noncallable. Duration and convexity bond math wiley online library. A bond is an instrument of indebtedness that obliges the bond issuer borrower to repay the lender creditor the borrowed assets plus the interest within a certain period of time fabozzi, 2000, p.
In more technical terms, bond duration is measurement of interest rate risk. Lecture 11 duration, convexity and immunisation reading. However, positive convexity does not necessarily lead to. Bond prices change inversely with interest rates, and, hence, there is interest rate risk with bonds.