Transcript Stock Data - Business Mathematics

Written By
Dr. Richard B. Thompson
Department of Mathematics
University of Arizona
Published and Distributed by
The
Mathematical Association of America
Business Projects By
Dr. Christopher G. Lamoureux
Department of Finance
University of Arizona
Part 1: Probability & Simulation
DOWNLOADING
HISTORICAL DATA
Title page
ON STOCK PRICES
Updated June 21, 2004. For distribution
only to licensed users of Mathematics for
Business Decisions, Part 1, Release 1.0.
This file contains directions for downloading historical data on
stock prices. It is intended for use with Project 2, Stock Option Pricing, in
Part 1 of Mathematics for Business Decisions.
YAHOO SITE
BUSINESS WEEK SITE
Mathematics for Business Decisions materials may be used by
individuals for study or examination. Any redistribution is strictly
prohibited. Any use for group or organized instruction requires written
approval from the authors.
Mathematics for
Business Decisions
Part 1
Release 1.0, 2003
© 2003 by The Arizona Board of Regents for The University of Arizona. All rights reserved.
Downloading Stock Records. Yahoo
Downloading Stock Records, Yahoo
1. YAHOO
The web site http://finance.yahoo.com/q/hp is a good source for
historical data on stock prices. We will illustrate the use of this site, as visited
on January 11, 2002, with the Walt Disney data for the Class Project. The
project calls for 8 years of weekly data, ending on Friday, January 11, 2002.
The site first requests the stock symbol DIS.
1. Enter DIS.
2. Click on Go
Problems with the Yahoo
site may occur with Netscape
browsers. If this happens, try
Internet Explorer.
DIS
Back to MBD Part 1
Business Background
finance.yahoo.com/q/hp
Back to MBD Part 1
Projects
(material continues)
Back to Project 2
Histograms
Start

Downloading Stock Records. Yahoo: page 2
Yahoo
3. Click Downloading,
on
Historical Prices.
4. Enter the starting
and ending dates.
6. Click on
Get Prices.
5. Select Weekly.
Yahoo displays weekly closes for Fridays, but labels the weeks with
the preceding Monday. The closing price on Friday, January 11, 2002 is
listed for “Week of” Monday, January 7, 2002. The starting date for our data
is automatically moved back to the Monday before January 11, 1994.
Back to MBD Part 1
Business Background
finance.yahoo.com/q/hp
Back to MBD Part 1
Projects
(material continues)
Back to Project 2
Histograms

Start

Downloading
StockYahoo
Records. Yahoo: page 3
Downloading,
Adjusted close on January 11, 2002
Actual close on January 11, 2002
Monday
What is the “adjusted close?” Yahoo starts on the date of a site visit,
assumes that all cash dividends have been reinvested, and then adjusts actual
Friday closes to account for the effect of stock splits and dividends.
Back to MBD Part 1
Business Background
finance.yahoo.com/q/hp
Back to MBD Part 1
Projects
(material continues)
Back to Project 2
Histograms

Start

Downloading Stock Records.Downloading,
Yahoo:
page 4
Yahoo
Avg. Vol.
Dividend paid
Actual close on
November 30, 2001
Adjusted close on
November 30, 2001
Monday
Back to MBD Part 1
Business Background
finance.yahoo.com/q/hp
Back to MBD Part 1
Projects
(material continues)
Back to Project 2
Histograms

Start

Downloading StockDownloading,
Records.
Yahoo: page 5
Yahoo
In our example, the actual and adjusted closing prices agree back to
the week of Monday, December 3, 2001. Walt Disney rose $1.88 from
$20.47 on Friday, November 30 to $22.35 on Friday, December 7.
However, the $0.21 dividend paid on Wednesday, December 5 during this
period, increased the actual gain to $2.09. Subtracting this from $22.35
gives a value of $20.26. This is the adjusted close for Friday, November 30
(the week of Monday, November 26), rounded to whole cents.
Continuing these adjustments back to January 14, 1994 (the week
of January 10, 1994), Yahoo finds an adjusted close of $14.9513. Perhaps
“adjusted value” would be a better term than adjusted close. The
interpretation is that $14.95 invested in Walt Disney stock on January 14,
1994, would be worth the adjusted closing price on the date of our site
visit.
Back to MBD Part 1
Business Background
finance.yahoo.com/q/hp
Back to MBD Part 1
Projects
(material continues)
Back to Project 2
Histograms

Start

Downloading Stock Records.
Yahoo:
page 6
Downloading,
Yahoo
Since the Yahoo site computes adjusted closing prices backward
from the date of the site visit, the adjusted closes may change from one site
visit to the next. This will not be a problem for us, since our only interest in
historical closing prices involves the ratio of one adjusted weekly close to
that of the preceding week. Any slight variation in the adjusted closes will
have no significant effect on estimated option values. The displayed
closing prices will be the same, no matter when the site is visited.
Once the historical data for a stock is displayed, on the screen, you
can save the records as an Excel spreadsheet. To do this, scroll down to the
end of the records and click on Download Spreadsheet Format. This will
export the data in a generic spreadsheet format. Save this exported file in
some convenient folder, and then open it in Excel. Once this is done, the
data can be edited and saved as an Excel file.
Back to MBD Part 1
Business Background
finance.yahoo.com/q/hp
Back to MBD Part 1
Projects
(material ends)
Back to Project 2
Histograms

Start
Downloading Stock Records. Business Week
Downloading Stock Records, Business Week
1. BUSINESS WEEK
A web site maintained by Business Week can also be used to obtain
historical data on stock prices.
http://host.businessweek.com/businessweek/Historical_Quotes.html
We will illustrate the use of this site with our Class Project data for
Walt Disney stock. Enter the stock symbol, DIS.
Back to MBD Part 1
Business Background
Click on Get Report
Back to MBD Part 1
Projects
Problems with the Business Week site may occur with
Netscape browsers. If this happens, try Internet Explorer.
host.businessweek.com/businessweek/Historical_Quotes.html
Back to Project 2
Histograms
(material continues)
Start

Downloading
StockBusiness
Records.
Business Week: page 2
Downloading,
Week
Enter the beginning and ending dates of the period for which you
want records, and select the desired frequency of the price data.
IMPORTANT, in order to get accurate data you must use an ending date that
is one week later than
January 11, 2002.
Back to MBD Part 1
Business Background
01/18/02
Back to MBD Part 1
Projects
Click on Get
Quotes
Back to Project 2
Histograms
(material continues)
host.businessweek.com/businessweek/Historical_Quotes.html

Start

Downloading
StockBusiness
Records.
Business Week: page 3
Downloading,
Week
The historical data is displayed from start to end, with Friday dates.
The close on Friday, January 11, 2002 is is the actual closing price on that
date. The “close” and all other data for Friday, January 18, 2002 is not
correct, and should be ignored.
Actual Close
Ignore Entire Row
Back to MBD Part 1
Business Background
Back to MBD Part 1
Projects
Back to Project 2
Histograms
(material continues)
host.businessweek.com/businessweek/Historical_Quotes.html

Start

Downloading
StockBusiness
Records.
Business Week: page 4
Downloading,
Week
To work with the Business Week data, use your internet browser to
save the page as an HTML file on some drive in your computer. Open this
file in Excel, and use Save As to save the file as a Microsoft Excel Workbook.
Delete all unneeded rows and columns in the Excel file. This should
include the final row with data for Friday, January 18, 2002.
Weekly Prices
Date
Open High Low
11/23/01
11/30/01
12/7/01
12/14/01
12/21/01
12/28/01
1/4/02
1/11/02
21.25
21.15
20.47
22.00
21.25
20.95
20.95
22.95
21.91
21.50
22.90
22.65
21.29
21.15
22.75
23.60
20.41
19.75
19.50
20.37
20.41
20.44
20.55
21.60
Close Volume
21.00
20.47
22.35
20.97
20.68
20.95
22.70
21.87
Back to MBD Part 1
Business Background
38,146,700
32,772,700
48,460,900
41,963,900
47,038,300
20,495,700
37,933,500
40,772,100
host.businessweek.com/businessweek/Historical_Quotes.html
Back to MBD Part 1
Projects
Back to Project 2
Histograms
(material continues)

Start

Downloading
StockBusiness
Records.
Business Week: page 5
Downloading,
Week
Comparing the Business Week data with that from the Yahoo site,
we see that Business Week does not adjust for the payment of stock
dividends. However, it does adjust values in all columns, including “close,”
for stock splits.
Due to the lack of adjustment for dividends, weekly ratios from the
Business Week site will not be exactly the same those from the Yahoo site.
The difference in computed option values from the two historical data sites
will be insignificant. It is preferable to use ratios from the Yahoo site, but
either set of data will produce acceptable ratios for your team project.
Business Week always adjusts closing prices from the time of the
site visit. This can cause a problem if the there has been a stock split between
the starting date of your option and the date that you download the data. It is
safer to use the Yahoo site to obtain the actual closing price of the stock at
the start of your option.
Back to Project 2
Histograms
Back to MBD Part 1
Back to MBD Part 1
Business Background
Projects
host.businessweek.com/businessweek/Historical_Quotes.html
(material ends)

Start
Blank