Dipartimento di Impresa e Management
Cattedra di Matematica Finanziaria
IMMUNIZATION AND HEDGING OF FIXED-INCOME SECURITIES IN COMPARISON
RELATORE
Prof. Gennaro Olivieri
CANDIDATO
Gianmarco Vitiello
Matr. 187381
ANNO ACCADEMICO 2016/2017
TABLE OF CONTENTS
Introduction
I. Chapter 1: Basic concepts 1. Interest Rate 2. Bond 3. Duration
II. Chapter 2: Immunization 1. Investment Accumulation and Duration 2. Classic Immunization Theory 3. Master Immunization
III. Chapter 3: Hedging fixed income securities 1. Introduction to Hedging 2. Interest Rate Futures 3. Hedging with Duration and Convexity
Conclusion
References
2 INTRODUCTION At the basis of this thesis there is the analysis of two important strategies implemented by portfolio managers in order to cover the risk of the interest risk, that is the immunization theory and the hedging of fixed-income securities. In particular the two arguments are presented from a theoretical point of view by treating important theorem of the immunization and the basis of the use of the derivatives such as the interest rate future. The motivations that allow to be interested in this subjects have two different aspects. First, I like to solve problem and face complexities: during my three-years undergraduate program I satisfy this aptitude in quantitative exams such as financial mathematics and markets and derivatives. Second, in a more and more globalized and at the same time more fragile and breakable economy, I have been interested in how to face the uncertainty technically. The objective of the thesis is the introduction of two different strategies in facing the uncertainty in the fixed income market and, finally, a comparison between them in order to show the strength points and weaknesses. The thesis is divided into three chapters, each one divided into three paragraphs: the first paragraph aim to introduce the basic concepts of financial mathematics applied by the strategies. The first paragraph treats the interest rate and how to compute it, the second introduces to the structure of a bond and how the interest rate affects the value of a bond. The third paragraph is focus on the two indicators of the volatility of a bond, namely the duration and the convexity. The second chapter introduces with the first paragraph the concept of investment accumulation and investment duration, then the second paragraph is focus on the Fisher and Weil’s theorem and on the Redington’s theorem of the immunization. Finally, the third paragraph of the second chapter points out the Vasicek and Fong’s discoveries, namely the general theorem of immunization and its theorization by not implying additive shifts but random shifts of the interest rate. The third chapter starts with an overview of the derivative world in the first paragraph. The second paragraph introduces the interest rate futures and, in conclusion the third one points out the theory of the hedging by applying the duration and the convexity in order to be cover by the interest rate volatility. Thanks to this thesis it has been possible to analyze deeply two important strategies applied in the world of the fixed income and, in the conclusion chapter, to make some comparison in real world applications of the two strategies.
3 I. BASIC CONCEPT
1. Interest Rate The “Interest Rate” is the ratio between the Interest and the Present value, in which the Interest is computed by subtracting the Present value to the Future value; and represents the percentage return than an investor obtains in a financial operation. A financial operation is an exchange of two different amounts of money in different periods of time and it can be understood, in regard of who supplies or who demands, as “Investment operation” in the former case or as “Financing operation” in the latter case.
In an Investment operation, any investor that owns a given amount of money “x”, decides to forgo this amount at time “t0”, in order to receive a greater amount of money “y” at time “t1”. This statement can be represented by the following expression:
x y t0 t1 where the value x is the “Present value” (or Initial investment), and the value y is the “Future value”. Hence, the following example expresses, given the features of a contract, how to compute the Interest rate: • suppose a farmer has $10,000 dollars and invests this amount in a contract that will provide him $10,500 dollars back after one year: the interest rate will be 5%.
In a Financing operation, a borrower, that needs money to finance a project, obligates himself to return an amount of money back at t1, in order to receive, at t0, a necessary amount of money to finance a project. The difference between the Future value and the Present value is the “Discount”. The discount rate is defined as the ratio between the Discount and the Future value. • For instance, a company needs to finance a positive-NPV project and decides to issue a Zero- Coupon Bond, whose maturity1 is in one year with face value2 of $1.000. The company receives
$950 at t0. So, the discount rate is 5%.
Summarizing the two financial operations discussed so far, what distinguishes them is only the point of view of the person that submits the financial transaction. In fact, there is a relation between the interest rate and the discount rate. Analytically it is stated by the following expressions: