After collecting the data, our group calculated the retums of these assets, analyzed the correlation coefficient from various perspectives, and computed the portfolio mean and variance f
Trang 1THE STATE BANK MINISTRY OF EDUCATION
HOCHIMINH UNIVERSITY OF BANKING
:
HOCHIMINH UNIVERSITY OF BANKING
MANAGEMENT APPLICATION THE GROUP PROJECT REPORT
Major / Specialization: Insurance — Finance — Banking
Trinh Trac Quynh - 110102210081 Khưu Nguyễn Khai Tri - 110102210036 Tran Khanh Linh - 110102210066
Võ Nguyễn Quý Tiên - 110102210031 Nguyễn Trần Hải Anh - 120603210006 Trần Thị Hồng Nhung - 120603210129
Hỗ Tiến Dương - 110320210038 Nguyễn Như Phát - 120603210132
Lê Trần Minh Thư - 120603210161
Lecturer: Ha Binh Minh
Ho Chi Minh City, November - 2024
Trang 2Table of Contents
1H PORTEOLIO MEANS AND VARIANCES OE N=2 ASSETS che 5
1V PORFORLIO MEANS AND VARIANCES OF N=4 ASSETS Hi 7
Trang 3L OVERVIEW
In this chapter, we delve into the fundamental principles of portfolio calculations, beginning with a straightforward example involving two assets, they are stocks: VINAMILK (VNM) and VINGROUP (VIC) We gathered historical data on their closing prices for the three most recent months from 6/8/2024 to 5/11/2024 After collecting the data, our group calculated the retums of these assets, analyzed the correlation coefficient from various perspectives, and computed the portfolio mean and variance for this pair of assets Subsequently, we experimented with the case of N assets (GAS and VCB); everything becomes convenient when using matrix notation and exploiting Excel's matrix handling capabilities
PetroVietnam Gas Corporation (GAS, PV Gas) is a Vietnam National Oil and Gas Group member unit PV Gas mainly operates in gathering, transporting, storing, processing, exporting, importing, and trading gas and gas products Its stock code is GAS Vietcombank
is the largest joint-stock commercial bank in Vietnam, with nearly 23,000 employees (2023 December), and offers a wide range of products and services, from deposit to lending activities with a network of branches and transaction offices spanning 50 of the 63 provinces across the country, the stock code is VCB Vinamilk, formally the Vietnam Dairy Products Joint Stock Company, is the largest dairy company in Vietnam, and the stock code is VNM The largest conglomerate in Vietnam, Vingroup Joint Stock Company, concentrates on
technology, industrial, real estate development, retail, and healthcare services The largest
conglomerate in Vietnam, Vingroup Joint Stock Company, concentrates on technology,
industrial, real estate development, retail, and healthcare services, and the stock code is VIC
In this section, we compute the return statistics for VINAMILK (stock symbol VNM) and VINGROUP (VIC) Here is the price and the return data
ILI Price and returns for VNM and VIC
These data give the closing price of two stocks from 6" August 2024 to 5" November 2024
and our group calculated the return based on the formula:
t
Hine
At the top section of the Excel sheet, we focus on calculating the return statistics for each
stock The monthly return reflects the percentage return an investor would earn by buying the stock at the end of a specific month (t-1) and selling it at the end of the next month
Trang 4
Figure 1 Historical data and Price and Returns For VNM and VIC Stock
We assume that historical performance provides valuable insights into future return patterns Based on this, the average of past data is treated as an estimate of the expected monthly retum for each stock Similarly, the historical data is used to infer the variance of potential
future returns We used the AVERAGE, VAR.S, and STDEV.S functions to perform these
calculations in Excel
The results are presented in the table below:
PRICE AND RETURNS FOR VINAMILK AND VINGROUP
IN 3 MONTHS FROM 6/8/2024- 5/11/2024
Figure 2 Price and Return
Firstly, the monthly mean retum of the two stocks represents the percentage profit or loss an
investor would achieve The monthly return for VNM is -0.166%, and for VIC, it is 0.000%,
calculated using the AVERAGE function for each stock's historical data Secondly, the monthly variance was computed using the VAR.S function, and from these results, the monthly standard deviation for each stock was determined
Trang 5Using the monthly figures as a basis, the annual values were calculated by multiplying the monthly figures by 12 months
IL2 Covariance and Correlation
Next, our group wants to calculate the covariance of the returns and present it in the table
below: The column Return minus average contains the return of VNM, VIC, and the
Product First is the return minus the average of VNM and VIC, which we calculated by using the stock return of each transaction minus the monthly mean of each stock Secondly, the Product column contains the multiple of returns minus the average of VNM and VIC
COMPUTING COVARIANCE AND CORRELATION
Figure 3 Covariance and Correlation of VNM and VIC Stocks
Next, our group defined the Covariance and Correlation as follows:
Covariance
-D5:D67)
Trang 62.3 The different view of the Correlation Coefficient
Another way to look at the correlation coefficient is to graph the VNM and VIC retums on the same axes and then use the Excel Trendline facility to regress the returns of VNM on those of VIC so our group has the graph below:
Graphing VIC (y-axis) against VNM (x-axis)
y = 0.1438x + 0.0002 R* = 0.0132
Figure 4 Trendlines of VNM and VICStocks
II PORTFOLIO MEANS AND VARIANCES OF N=2 ASSETS
During this part, we calculate the portfolio of VIC and VNM mean and variance based on the
last 3 months This portfolio contains 50% of each share, 50% of VIC, and 50% of VNM
Therefore, before calculating the returns, we need to add this information first
3.1 Means and Standard Deviation
CALCULATING THE MEANS AND STANDARD DEVIATIONS OF PORTFOLIO
Portfolio of VNM| 0.5|
Portfolio of VIC_ | 0.5|
Trang 7
To ensure accuracy for future use, we will calculate B3 by taking | minus B2 to calculate the exact percentage After we determine the portion of our portfolio, what will be the mean and variance of this portfolio? It is worth doing the brute force calculations at least once in Excel:
Figure 5 Means and Standard Deviation of a Portfolio
The mean portfolio return is exactly the average of the mean returns of the two assets:
It is calculated by multiplying the portfolio of VNM by VNM’s retum and then plus
with portfolio of VIC by VIC’s return Or we can write in the formula:
Expected portfolio return = E(rp) = 0.5E(rvnw) + 0.5E(rvic) 3.2 Porforlio Returns
In general, the mean return of the portfolio is the weighted average return of the component
stocks
Mean return, variance return, standard deviation, and covariance are calculated by using data
from each table for each stock, with the functions or Average, VAR.S, and STDEV.S Then
the data from the table also be applied to calculate the portfolio mean return, portfolio return variance, and portfolio retum standard deviation For these data, there are two ways to measure which are demonstrated in the figure above
3.3 Efficient frontier of the portfolio
Trang 8A frequently performed exercise is to plot the means and standard deviations for
various portfolio proportions x To do this we built a table using Excel’s Data|What-If|
DataTable:
Portfolio mean return
-0.08%|=AVERAGE(D6:D68) -0.08%]=B2*G6+B3*H6
Portfolio return variance
0.0000896994/=V AR.S(D6:D68) 0.0000§96994|=B2^2*G7+B3ˆ2*H7+2*B2*B3*G9
Portfolio return standard đeviation
0.0094710|=SQRT(G16) 0.0094710|=STDEV.S(D6:D68)
0.0094710=STDEV.S(D6D68§)
Portfolio E(r,) and Ø, 0.10%
°
> °
sf 005% “
sy eo
E 0.00% °
& — o.00p00% 0.50000% 100000%, © 1.S0000% 2 00000% 2.50000%
c -0.05% ° zs Value) Axis
s x Horizontal (Value) Axis
3 Se
Ễ - °
E -010% °
2 °
£ °
§ 015%
® 0.20% °
° ° 0.25% °
Portfolio standard deviation p
a7 n 02a
Figure 6 Efficient frontier of the portfolio (N=2)
IV PORFORLIO MEANS AND VARIANCES OF N=4 ASSETS
4.1 Formula
This section calculates the mean and variance of a specific number of assets, which is different from the previous section The expected return of the portfolio whose proportions are given by X is the weighted average of the expected returns of the individual assets:
E(Œ.)E > x,Elri
Trang 9which, in matrix notation, can be written as E(ry}= È_ x,Efr,) = xTE(r) = E(r)'x
i=1
The portfolio’s variance is given by:
N N N Var(r)= È› (x¿¿ï)f Var(r,)¿+2 2) Ð; x,.x,Cov(x,,x,)
i=1 i=1 j=i+l
Each asset’s variance appears once, multiplied by the square of the asset's proportion in
the portfolio; the covariance of each pair of assets appears once, multiplied by twice the
product of the individual assets’ proportions Another way of writing the variance is to
use the notation: Var(ri)=%i , COV(Iij)= Øụ
4.2 Covariance Between Two Portfolios
In Excel formulas, this is the array function MMult(MMult(x,S),Transpose(y))
Portfolio Calculations Using Matrices—An Example: Four risky assets have the
following expected returns and variance-covariance matrix:
A FOUR-ASSET PORTFOLIO PROBLEM
Mean Variance-covariance, S returns
E(r) 0.000070 0.000007 0.000014 0.000016 0.0970%| {=TRANSPOSE(N = 4'1S3:V3)} 0.000007 0.000273 0.000051 -0.000001 -0.1522%
0.000014 0.000051 0.000125 0.000018 -0.1592%
0.000016 -0.000001 0.000018 0.000202 0.0098%
We are calculating the two portfolios’ means, variances, and covariance We use the
function MMult for the matrix multiplications and the array function Transpose
Portfolio x and y statistics: Mean, variance, covariance, correlation
Covariance (xy) 0.0000345 {=MMULT(MMULT(@8:E3,A3:D6), TRANSPOSE(B9:E9))}
0.0000463|{=MMULT(MMULT(9:E9.A3:D6),TRANSE
We can now calculate the standard deviation and return of combinations of portfolios x
and y We have calculated the means, variances, and the covariance of the returns of
the two portfolios in the table below:
Trang 10
Proportion of x 03
Portfolio vaianes Portioko standard deviation 0, 00000551ƑP18018134(1818/20E13-01181/.818/814 0.743067} =30RTB20)
Table of returns (using Data Table)
Figure 7: Efficient frontier of the portfolio (N=4)
V ENVELOPE PORTFOLIO
An envelope portfolio is a portfolio of risky assets that gives the lowest variance of return of all portfolios having the same expected return An efficient portfolio is a portfolio that gives the highest expected return of all portfolios having the same variance Mathematically, we may define an envelope portfolio as follows: For a given return « = E(",), an efficient portfolio p = [X,, X, , Xy | is one that solves
To show that the concepts of envelope and efficient portfolio are non-trivial, we show that the two portfolios whose combinations are graphed in the previous examples are not either envelope or efficient This is easy to see if we extend the data table to include numbers for the individual stocks: We can see that stock VNM and stock VCB fall outside the frontier created by combinations of portfolios x and y Thus x and y cannot be efficient portfolios
Trang 110.10% NN .°
a ° + 0.00% +
= `
E °
5 °
a © 0.10% °
3 £ "6 a
2
a 0.20% <i e
x "
£ 0.30% °%
=
S °
0.40%
0.0% 0.5% 1.0% 1.3% 2.0% — 2.5% 3.0 5% 4.0%
ma-e£^f^ =e¬=2^rd deviation
Figure 7 Envelope Portfolio
VI CONCLUSION
In conclusion, all four stocks are worth investing in However, we have to consider the proportion before investing in the portfolio Excel can also be a handy tool for portfolio calculations and offers a range of benefits It provides a flexible and accessible platform that can handle a variety of financial calculations Excel’s built-in functions and formulas make
calculating portfolio returns, variances, standard deviations, and correlations easy Moreover,
Excel’s data visualization tools can help understand a portfolio's risk and return trade-off and
assist in making informed investment decisions However, while Excel is a powerful tool, it
is important to remember that the accuracy of the calculations depends on the quality of the input data Therefore, investors should ensure they use reliable and up-to-date data when using Excel for portfolio calculations
VIL REFERENCES
Benninga, S (2014) FINANCIAL MODELING (4 ed.) The MIT Press