Chapter 27 The Basic Tools of Finance

Finance is the field that studies how people make decisions regarding the allocation of resources over time and the handling of risk.

27.1 PRESENT VALUE: MEASURING THE TIME VALUE OF MONEY Present value refers to the amount of money today that would be needed to produce, using prevailing interest rates, a given future amount of money.

27.1 PRESENT VALUE: MEASURING THE TIME VALUE OF MONEY The concept of present value demonstrates the following: Receiving a given sum of money in the present is preferred to receiving the same sum in the future. In order to compare values at different points in time, compare their present values. Firms undertake investment projects if the present value of the project exceeds the cost.

27.1 PRESENT VALUE: MEASURING THE TIME VALUE OF MONEY If r is the interest rate, then an amount X to be received in N years has present value of: X/(1 + r) N

27.1 PRESENT VALUE: MEASURING THE TIME VALUE OF MONEY Future Value –The amount of money in the future that an amount of money today will yield, given prevailing interest rates, is called the future value.

FYI: Rule of 70 According to the rule of 70, if some variable grows at a rate of x percent per year, then that variable doubles in approximately 70/x years.

27.2 MANAGING RISK A person is said to be risk averse if she exhibits a dislike of uncertainty.

27.2 MANAGING RISK Individuals can reduce risk choosing any of the following: –Buy insurance –Diversify –Accept a lower return on their investments

Figure 1 Risk Aversion Wealth 0 Utility Current wealth $1,000 gain $1,000 loss Utility loss from losing $1,000 Utility gain from winning $1,000

The Markets for Insurance One way to deal with risk is to buy insurance. The general feature of insurance contracts is that a person facing a risk pays a fee to an insurance company, which in return agrees to accept all or part of the risk.

Diversification of Idiosyncratic Risk Diversification refers to the reduction of risk achieved by replacing a single risk with a large number of smaller unrelated risks.

Diversification of Idiosyncratic Risk Idiosyncratic risk is the risk that affects only a single person. The uncertainty associated with specific companies.

Diversification of Idiosyncratic Risk Aggregate risk is the risk that affects all economic actors at once, the uncertainty associated with the entire economy. Diversification cannot remove aggregate risk.

Figure 2 Diversification Number of Stocks in Portfolio 49 (More risk) (Less risk) Risk (standard deviation of portfolio return) Aggregate risk Idiosyncratic risk 30

Diversification of Idiosyncratic Risk People can reduce risk by accepting a lower rate of return.

Figure 3 The Tradeoff between Risk and Return Risk (standard deviation) Return (percent per year) 50% stocks 25% stocks No stocks 100% stocks 75% stocks

27.3 ASSET VALUATION Fundamental analysis is the study of a company’s accounting statements and future prospects to determine its value.

27.3 ASSET VALUATION People can employ fundamental analysis to try to determine if a stock is undervalued, overvalued, or fairly valued. The goal is to buy undervalued stock.

Efficient Markets Hypothesis The efficient markets hypothesis is the theory that asset prices reflect all publicly available information about the value of an asset.

Efficient Markets Hypothesis A market is informationally efficient when it reflects all available information in a rational way. If markets are efficient, the only thing an investor can do is buy a diversified portfolio

CASE STUDY: Random Walks and Index Funds Random walk refers to the path of a variable whose changes are impossible to predict. If markets are efficient, all stocks are fairly valued and no stock is more likely to appreciate than another. Thus stock prices follow a random walk.

23 FIGURE 27-4 RELATIONSHIP OF CANADIAN STOCK PRICES TO THEIR PAST VALUES Source: DRI/McGraw-Hill Macroeconomic Database

FIGURE 1. RELATIONSHIP OF Shanghai STOCK PRICES TO THEIR PAST VALUES

27 FIGURE 27-5 RELATIONSHIP OF S&P 500 INDEX TO PAST VALUES Source: Haver Analytics Macroeconomic Database

上海证券家数深圳证券家数 截止： 2008 年 4 月 18 日

Summary Because savings can earn interest, a sum of money today is more valuable than the same sum of money in the future. A person can compare sums from different times using the concept of present value. The present value of any future sum is the amount that would be needed today, given prevailing interest rates, to produce the future sum.

Summary Because of diminishing marginal utility, most people are risk averse. Risk-averse people can reduce risk using insurance, through diversification, and by choosing a portfolio with lower risk and lower returns. The value of an asset, such as a share of stock, equals the present value of the cash flows the owner of the share will receive, including the stream of dividends and the final sale price.

Summary According to the efficient markets hypothesis, financial markets process available information rationally, so a stock price always equals the best estimate of the value of the underlying business. Some economists question the efficient markets hypothesis, however, and believe that irrational psychological factors also influence asset prices.

Questions for reviews 1. present value, future value? 2. Risk averse? 3. The efficient markets hypothesis? 4. Random walk? ( Random walk means that the changes in stock prices are impossible to predict from available information. ) 5. Market irrationality? (Assets markets are driven by the “animal spirits” 本能冲动 of investors—irrational waves of optimism and pessimism.)

1. 利率为 7% 。用现值的概念比较 10 年中得到的 200 美元与 20 年中得到的 300 美元。

2. 人们从保险市场中得到了什么利益？阻碍保险公 司完全发生作用的两个问题是什么？ 3. 什么是多元化？股东从 1 ～ 10 种股票中多元化还 是从 l00 ～ l20 种股票中多元化？ 4. 比较股票和政府债券，哪一种风险更大？哪一种 能够带来更高的平均收益？ 5. 股票分析师在确定一股股票的价值时应该考虑哪 些因素？ 6. 叙述有效市场假说，并给出一个与这种理论一致 的证据。 7. 解释那些怀疑有效市场假说的经济学家的观点。