Search for another Company Symbol?

AT and T Historical Volatility

Chapter II: Understanding Price Volatility behaviour is essential to assessing the risk associated with positions across different time spans.

Prev. Co. Next Co.
Daily Volatility = Price Range as a percent of the daily average price. of AT and T

Volatility is defined as the price range for a period, divided by the average price for the period:

For instance, on 3/4/2010 the average price was 24.9 with a range of 0.20, indicating a Daily Volatility of 0.8%. The Daily Volatility is obtained by dividing the daily range by the daily average. A longer Volatility period such as Weekly Volatility is obtained by dividing the weekly price range by the weekly mean price. This is a different concept from the weekly average of daily volatility.

The red plot shows the actual price. The remaining marks on the plot correspond to the Volatility measured across several time intervals.

Investors often make a distinction between the concept of Volatility, and the concept of Risk. Academics define them to be exactly equivalent, but as can be seen here, there is good reason to distinguish between the levels of volatility or risk experienced across different time frames. During 26 years, the Average Quarterly Volatility of T stock price has been 18% while the Average Daily Volatility has been 2%.



Prev. Co. Next Co.
Volatility Curve of AT and T

If you have ever seen a "yield curve" you should be able to understand the concept behind this "yield curve". Each Volatility Curve is a snapshot in time. From left to right, each position plots the Volatility associated with increasing intervals of time. The relationship between the length of time, and the expected change in price, is not linear, as is demonstrated by this chart.



Prev. Co. Next Co.
T:  Daily Volatility Histogram

This histogram is a frequency distribution of Daily Volatility, corresponding to the green points on the first chart on this page.



Prev. Co. Next Co.
Quarterly Volatility Histogram of AT and T

Similarly, the purple points on the top chart, the Quarterly Volatility Values, are subjected to frequency distribution here.

For Subscribers: Refined Analysis of AT and T Volatility and Risk Behavior

Refined Volatility Risk Analysis for T :


Companies in the News:

In the news, Thursday, March 18, 2010: An unfavorable condition has developed with MicroSoft, ticker symbol MSFT. Also, there are breaking events concerning AOL Time Warner (TWX) and Mylan Inc. (MYL)

More T Technical Analysis Topics

T Price Predictions

Support and Resistance Levels

Politics and Prices of T

Japanese Candlestick Analysis

T Classical Analysis of Time Series

T Historical Volume

T Seasonal Trends

Market Sentiment

Back to T Table of Contents


Information on public pages is delayed. Associates of Hybrid Technical may hold positions in issues covered here. These reports are not to be used for stock-picking or investment decision support. Any such use is strictly prohibited.



Notice: Pages available to the public on this site are for entertainment and academic purposes only. We do not advocate investment in common stock. We do not recommend the purchase or sale of this or any other issue. Research shows that most people who invest in common stock will lose money. Charts and concepts are property of Hybrid Technical. All Rights Reserved. All Content is Copyright 2008 by Hybrid Technical

.