Tuesday, January 31, 2023

Why is the stock of Goodyear Tire & Rubber Co. So Volatile?

Goodyear (GT) is a very volatile stock with a beta of 1.86, measured using a linear regression model. This linear regression model used monthly returns for Goodyear and the Vanguard S&P 500 Index ETF (VOO) from June 2019 to January 2023. This beta is one of the highest I have encountered among the stocks I cover (Exhibit 1).

Image: 90% Sustainable Material Demonstration Tire

Source: Goodyear Tire & Rubber Co.


The stock is heavily dependent on the discretionary spending of the consumer. In a downturn, car sales drop, thus affecting Goodyear's sales. The replacement tire sales also drop in an economic slowdown, affecting the company. These might be the reasons behind the high volatility.   

Note: Please click on the image to see an enlarged version.

Exhibit 1: Beta of Stocks in Industrial, Consumer Staples, Technology, and Consumer Discretionary Sectors  

Source: Data Provided by IEX Cloud, Author Calculations using Microsoft Excel & RStudio


Here's the output from the linear regression model:

Call:
lm(formula = GT_Monthly_Return ~ VOO_Monthly_Return, data = VOOandGT)

Residuals:
     Min       1Q   Median       3Q      Max 
-0.21099 -0.10456 -0.01782  0.07052  0.55012 

Coefficients:
                    Estimate Std. Error t value Pr(>|t|)    
(Intercept)        -0.008481   0.021853  -0.388      0.7    
VOO_Monthly_Return  1.869864   0.379106   4.932 1.33e-05 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

Residual standard error: 0.1425 on 42 degrees of freedom
Multiple R-squared:  0.3668, Adjusted R-squared:  0.3517 
F-statistic: 24.33 on 1 and 42 DF,  p-value: 1.326e-05

The coefficient for "VOO_Monthly_Return" is the beta for the stock.  This coefficient is also the slope of the line.  The monthly returns of Goodyear have been plotted against the returns of the Vanguard S&P 500 Index ETF (Exhibit 2). Exhibit 3 shows the residuals from the linear regression mode. There is a solid positive monthly return correlation of 0.61 between the Vanguard ETF and Goodyear. There is also a significant relationship between the monthly returns of the Vanguard ETF and Goodyear, with a p-value of 1.3e-05.     

Exhibit 2: Monthly Returns Plot of the Vanguard S&P 500 Index ETF and Goodyear Tires

Source: Data Provided by IEX Cloud, Author Calculations Using Microsoft Excel, and Graph Plotted Using RStudio


Exhibit 3: Residuals from the Linear Regression of the Vanguard S&P 500 Index ETF and Goodyear Tires Monthly Returns
Source: Data Provided by IEX Cloud, Author Calculations Using Microsoft Excel, and Graph Plotted Using RStudio



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