InvestorCraft's
Efficient Frontier
tool is a powerful portfolio optimizer that is based
on key concepts of modern portfolio theory.
Professor Harry Markowitz, a nobel-prize
winning economist, introduced the concept of the Efficient Frontier.
This tool analyzes trade-offs between risk and expected
return of various portfolios composed of various asset weightings. Changing asset weightings will change both
the expected return and expected risk (measured by standard deviation) of the
portfolio. The Efficient Frontier tool
analyzes all possible portfolio combinations (by varying asset weights) and
finds the ones that offer the best expected return for a given level of
risk. It plots these portfolios on a
curve called the Efficient Frontier. The Efficient Frontier curve corresponds to the most efficient investment strategies. Any given portfolio on the Efficient Frontier
is said to dominate all other possible portfolios that have either the same level
of expected return or standard
deviation. All results are based on analysis
of historical prices of each security in the portfolio.
After plotting the Efficient Frontier curve, the tool then
determines an optimal portfolio. It does
this by selecting the portfolio that falls at the point of tangency with the
straight line starting at the risk-free rate of return on the y-axis. This line, sometimes called the capital
market line, assumes that the investor will either invest in cash (at the
risk-free interest rate) or a portfolio on the efficient curve. The point of tangency maximizes the slope of
the capital market line, which is given by the equation:
Slope = (Return – RiskFreeRate)/ (StandardDeviation)
This slope is also known as the Sharpe Ratio, which is a
ratio of reward to risk. The higher the
Sharpe Ratio, the better. The Efficient
Frontier tool finds the point on the efficient frontier that maximizes the
Sharpe Ratio.
To use the Efficient Frontier Tool to analyze your portfolio,
perform the following steps:
- Select
the
Efficient Frontier
tool.
- Add
your securities to the list of portfolios, either by selecting the
security in the asset selection tree, or by using the search feature. Select the “Add” button or “Remove”
button to add or remove each security from the list.
- Once
you have added the securities, select the “Next” button.
- Select
the time range to analyze historical data for the analysis. It is important to select a time range
long enough to provide a good representation of stock price movements
under different market conditions (up and down). All results provided the tool are based on
price behaviors of this time period.
- Enter
the risk-free interest rate. This
is the rate it which you could invest your cash with no risk. The 10-year treasure rate is often used
here.
- If you
want to specify an allowed weight for any single security in the
portfolio, you can enter a minimum and maximum. These are optional, but if
you specify them, the tool will adjust its calculated theoretical optimal portfolio
(which may have asset weights outside your desired range) to fit within your
specified limits. The resulting
portfolio will be reported as the Adjusted Portfolio.
- Select
the “Calculate” button.
- At
this point, the tool will calculate the efficient frontier curve and the Optimal
Portfolio and Adjusted Portfolio (if you specified minimum/maximum weights).
The results are reported in several tables and graphs as follows:
Portfolio Details
|
Caterpillar Inc. |
CAT |
20.3 % |
23.7 % |
4.9 % |
3.1 % |
6.4 % |
|
Amgen |
AMGN |
7.1 % |
24.8 % |
-3.1 % |
1.0 % |
7.4 % |
|
Chevron Corp. |
CVX |
25.9 % |
19.0 % |
30.6 % |
26.4 % |
13.5 % |
|
Rockwell Automation Inc. |
ROK |
28.0 % |
27.6 % |
12.6 % |
10.0 % |
2.4 % |
|
Illinois Tool Works |
ITW |
10.8 % |
17.0 % |
-11.1 % |
1.0 % |
12.0 % |
|
Bank of America Corp. |
BAC |
17.2 % |
11.6 % |
66.0 % |
58.6 % |
58.2 % |
The Portfolio Details table shows
each asset in the portfolio and its characteristics, including:
·
Expected return – the expected annual return
based on the asset’s mean return over the time period analyzed.
·
Standard deviation – the standard deviation of
the asset over the time period.
·
Optimal Weight – the calculated weight of the
security to achieve the optimal point of tangency on the efficient frontier. Optimal weights can be negative, indicating
short selling.
·
Adjusted Weight – the calculated weight of the
security that adjusts the optimal weight to fit within the allowable range
specified by you.
·
Minimum Variance Weight – the calculated weight
of the security that results in the minimal standard deviation for the overall
portfolio.
The composition of three different portfolios is shown: Optimal, Adjusted and Minimum
Variance. The overall characteristics of each
portfolio are shown in the next table:
Metrics for Above
Portfolio Mixes
|
Optimal Portfolio |
22.4 % |
10.6 % |
1.716 |
2.101 |
|
Adjusted Portfolio |
20.4 % |
9.8 % |
1.668 |
2.087 |
|
Minimum Variance Portfolio |
17.2 % |
9.1 % |
1.439 |
1.889 |
|
Time period:
|
3 years
|
Single asset Maximum weight:
|
60.0 %
|
|
Risk free rate:
|
4.10 % |
Single asset Minimum weight:
|
1.0 %
|
This table shows the expected overall annual return and standard
deviation for each of the three portfolios.
Note that the optimal portfolio will always have the maximum Sharpe Ratio.
Also, note that the minimal variance portfolio is expected to have the
minimum standard deviation, but without regard to return. The ratio of expected return (Er) to standard deviation
(StDev) is shown as a reference point. It is similar to the Sharpe Ratio,
but does not take into account the offset of the return exceeding the risk-free rate.
The graph shows the efficient frontier curve (in blue),
which is all portfolios that dominate others at any given level of return or
standard deviation. It shows the
location of the optimal portfolio at the point of tangency on the efficient
frontier with the line that intersects the y-axis at the risk-free rate (in
green). It also shows the point for the
adjusted portfolio, which is always somewhat less "efficient" (since it is
constrained by your allowed minimum and maximum weights). The
minimum variance portfolio is located at the apex of the curve (left-most point).
For your reference, the tables of
correlation factors for all assets is also shown. This is useful reference information as you
study the data.
It is important to study and understand the tables and graph.
Some key points to look for:
- Study
the optimal portfolio numbers in the first two tables. It will show you the recommended
weighting of each asset in your portfolio to achieve a theoretical optimum
ratio of reward-to-risk. It is
theoretical since it is based on past history, which is unlikely to
exactly repeat itself. But it is a
good starting point. Often, the
optimal portfolio will have extreme weights that involve short selling.
- Study
the adjusted portfolio numbers if you specified minimum/maximum allowed
weights. It will usually be much
more practical, since confines the asset weightings to your specified range for each
asset. However, realize it is not
as efficient (in theory) as the optimal portfolio. The overall return will be less than
the optimal portfolio, and the Sharpe ratio will not be quite as good.
- Study
the minimum variance portfolio also.
It is the portfolio that provides the absolute minimum variance,
without regard to return. So you
can look at it as the lowest risk portfolio. Note how it has the lowest standard
deviation, which is a measure of volatility.
At this point, you may want to make adjustments to the portfolio by going back to the first page of the Efficient Frontier and
removing or adding assets to see how they contribute to better diversifying the portfolio. You can experiment with
a virtually unlimited variety of portfolios.
Finally, be aware that all results of the Efficient Frontier tool are based on past price
history behavior of each security, and that past history is often not an
indicator of future behavior. Market
conditions can change, as can managers of mutual funds and companies. This is why it is important to select a time
period for analysis that you feel will be a good representation or model for
the future. It is also why it is essential that you carefully research each individual
security on its own merits to understand its prospects for the future.
Once you are done building and analyzing the portfolio, you
can choose to save it if you wish. To do
this, select the “Save portfolio” button.
If you are not already logged-in, you will be prompted to log-in so that
the portfolio can be associated with your user-name. You can later reference this portfolio in
My Portfoliois,
and track its performance and perform further analysis on it in the
future.