Moneyweighted and timeweighted rates of return are two methods of measuring performance, or the rate of return on an investment portfolio. Each of these two approaches has particular instances where it is the preferred method. Given the priority in today's environment on performance returns (particularly when comparing and evaluating money managers), the CFA exam will be certain to test whether a candidate understands each methodology.
MoneyWeighted Rate of Return
A moneyweighted rate of return is identical in concept to an internal rate of return: it is the discount rate on which the NPV = 0 or the present value of inflows = present value of outflows. Recall that for the IRR method, we start by identifying all cash inflows and outflows. When applied to an investment portfolio:
Outflows
1. The cost of any investment purchased
2. Reinvested dividends or interest
3. Withdrawals
Inflows
1.The proceeds from any investment sold
2.Dividends or interest received
3.Contributions
Example:
Each inflow or outflow must be discounted back to the present using a rate (r) that will make PV (inflows) = PV (outflows). For example, take a case where we buy one share of a stock for $50 that pays an annual $2 dividend, and sell it after two years for $65. Our moneyweighted rate of return will be a rate that satisfies the following equation:PV Outflows = PV Inflows = $2/(1 + r) + $2/(1 + r)^{2} + $65/(1 + r)^{2 }= $50
Solving for r using a spreadsheet or financial calculator, we have a moneyweighted rate of return = 17.78%.
Exam Tips and Tricks
Note that the exam will test knowledge of the concept of moneyweighted return, but any computations should not require use of a financial calculator
It's important to understand the main limitation of the moneyweighted return as a tool for evaluating managers. As defined earlier, the moneyweighted rate of return factors all cash flows, including contributions and withdrawals. Assuming a moneyweighted return is calculated over many periods, the formula will tend to place a greater weight on the performance in periods when the account size is highest (hence the label moneyweighted).
In practice, if a manager's best years occur when an account is small, and then (after the client deposits more funds) market conditions become more unfavorable, the moneyweighted measure doesn't treat the manager fairly. Here it is put another way: say the account has annual withdrawals to provide a retiree with income, and the manager does relatively poorly in the early years (when the account is larger), but improves in later periods after distributions have reduced the account's size. Should the manager be penalized for something beyond his or her control? Deposits and withdrawals are usually outside of a manager's control; thus, a better performance measurement tool is needed to judge a manager more fairly and allow for comparisons with peers  a measurement tool that will isolate the investment actions, and not penalize for deposit/withdrawal activity.
TimeWeighted Rate of Return
The timeweighted rate of return is the preferred industry standard as it is not sensitive to contributions or withdrawals. It is defined as the compounded growth rate of $1 over the period being measured. The timeweighted formula is essentially a geometric mean of a number of holdingperiod returns that are linked together or compounded over time (thus, timeweighted). The holdingperiod return, or HPR, (rate of return for one period) is computed using this formula:
Formula 2.8 HPR = ((MV_{1}  MV_{0} + D_{1}  CF_{1})/MV_{0})
Where: MV_{0} = beginning market value, MV_{1} = ending market value,
D_{1} = dividend/interest inflows, CF_{1} = cash flow received at period end (deposits subtracted, withdrawals added back)
For timeweighted performance measurement, the total period to be measured is broken into many subperiods, with a subperiod ending (and portfolio priced) on any day with significant contribution or withdrawal activity, or at the end of the month or quarter. Subperiods can cover any length of time chosen by the manager and need not be uniform. A holdingperiod return is computed using the above formula for all subperiods. Linking (or compounding) HPRs is done by
(a) adding 1 to each subperiod HPR, then
(b) multiplying all 1 + HPR terms together, then
(c) subtracting 1 from the product:
Compounded timeweighted rate of return, for N holding periods
= [(1 + HPR_{1})*(1 + HPR_{2})*(1 + HPR_{3}) ... *(1 + HPR_{N})]  1.
The annualized rate of return takes the compounded timeweighted rate and standardizes it by computing a geometric average of the linked holdingperiod returns.
Formula 2.9
Annualized rate of return = (1 + compounded rate)^{1/Y}  1
Where: Y = total time in years
Example: TimeWeighted Portfolio Return
Consider the following example: A portfolio was priced at the following values for the quarterend dates indicated:
Date  Market Value 
Dec. 31, 2003  $200,000 
March 31, 2004  $196,500 
June 30, 2004  $200,000 
Sept. 30, 2004  $243,000 
Dec. 31, 2004  $250,000 
On Dec. 31, 2004, the annual fee of $2,000 was deducted from the account. On July 30, 2004, the annual contribution of $20,000 was received, which boosted the account value to $222,000 on July 30. How would we calculate a timeweighted rate of return for 2004?
Answer:
For this example, the year is broken into four holdingperiod returns to be calculated for each quarter. Also, since a significant contribution of $20,000 was received intraperiod, we will need to calculate two holdingperiod returns for the third quarter, June 30, 2004, to July 30, 2004, and July 30, 2004, to Sept 30, 2004. In total, there are five HPRs that must be computed using the formula HPR = (MV_{1}  MV_{0} + D_{1}  CF_{1})/MV_{0}. Note that since D_{1}, or dividend payments, are already factored into the endingperiod value, this term will not be needed for the computation. On a test problem, if dividends or interest is shown separately, simply add it to endingperiod value. The calculations are done below (dollar amounts in thousands):Period 1 (Dec 31, 2003, to Mar 31, 2004):
HPR = (($196.5  $200)/$200) = (3.5)/200 = 1.75%.
Period 2 (Mar 31, 2004, to June 30, 2004):
HPR = (($200  $196.5)/$196.5) = 3.5/196.5 = +1.78%.
Period 3 (June 30, 2004, to July 30, 2004):
HPR = (($222  $20)  $200)/$200) = 2/200 = +1.00%.
Period 4 (July 30, 2004, to Sept 30, 2004):
HPR = ($243  $222)/$222 = 21/222 = +9.46%.
Period 5 (Sept 30, 2004, to Dec 31, 2004):
HPR = (($250  $2)  $243)/$243 = 5/243 = +2.06%
Now we link the five periods together, by adding 1 to each HPR, multiplying all terms, and subtracting 1 from the product, to find the compounded time weighted rate of return:
2004 return = ((1 + (.0175))*(1 + 0.0178)*(1 + 0.01)*(1 + 0.0946)*(1 + 0.0206))  1 = ((0.9825)*(1.0178)*(1.01)*(1.0946)*(1.0206))  1 = (1.128288)  1 = 0.128288, or 12.83% (rounding to the nearest 1/100 of a percent).
Annualizing: Because our compounded calculation was for one year, the annualized figure is the same +12.83%. If the same portfolio had a 2003 return of 20%, the twoyear compounded number would be ((1 + 0.20)*(1 + 0.1283))  1, or 35.40%. Annualize by adding 1, and then taking to the 1/Y power, and then subtracting 1: (1 + 0.3540)^{1/2}  1 = 16.36%.
Note: The annualized number is the same as a geometric average, a concept covered in the statistics section.
Example: Money Weighted Returns
Calculating moneyweighted returns will usually require use of a financial calculator if there are cash flows more than one period in the future. Earlier we presented a case where a moneyweighted return for two periods was equal to the IRR, where NPV = 0.Answer:
For moneyweighted returns covering a single period, we know PV (inflows)  PV (outflows) = 0. If we pay $100 for a stock today, and sell it in one year later for $105, and collect a $2 dividend, we have a moneyweighted return or IRR = ($105)/(1 + r) + ($2)/(1 + r)  $100 = $0. r = ($105 + $2)/$100  1, or 7%.Moneyweighted return = timeweighted return for a single period where the cash flow is received at the end. If the period is any time frame other than one year, take (1 + the result), raised to the power 1/Y and subtract 1 to find the annualized return.

Investing
Learn Simple and Compound Interest
Interest is defined as the cost of borrowing money or the rate paid on a deposit to an investor. Interest can be classified as simple interest or compound interest. 
Investing
Overcoming Compounding's Dark Side
Understanding how money is made and lost over time can help you improve your returns. 
Investing
Breaking Down The Geometric Mean
Understanding portfolio performance, whether for a selfmanaged, discretionary portfolio or a nondiscretionary portfolio, is vital to determining whether the portfolio strategy is working or ... 
Investing
The Effective Annual Interest Rate
The effective annual interest rate is a way of restating the annual interest rate so that it takes into account the effects of compounding. 
Investing
How to Calculate Required Rate of Return
The required rate of return is used by investors and corporatefinance professionals to evaluate investments. In this article, we explore the various ways it can be calculated and put to use. ... 
Financial Advisor
A Guide on the RiskAdjusted Discount Rate
When a project or investment faces higher amounts of risk or uncertainty, it may be appropriate to utilize the riskadjusted discount rate. 
Investing
What Returns Can You Expect in the Stock Market?
Looking at the historical returns of the stock market helps you understand current stock returns. 
Investing
Internal Rate of Return: An Inside Look
The internal rate of return can be used to measure an compare capital projects, stock buyback programs, and investments to determine which will yield the most favorable return. 
Investing
How to Make the Time Value of Money Work for You
How to make the time value of money and power of compounding work for you. Here's a hint: Start saving now.