Exploring Tesla & Co. Stock Prices
By: Derek Hsu
Tags: Energy, Investing, Tesla, Stocks, Productivity

Tesla Model S, source: https://www.tesla.com/models

Exploring Tesla & Co. Stock Prices

There is a never-ending stream of stories on electric vehicles. As I keep reading stories about these high-flying stocks, I thought I would do a basic exploration of how stock prices of different companies in this space compare. Specifically, I will discuss price, cumulative return, and correlation data.

tldr: Tesla’s stock price has soared high above those of other EV companies. However, Workhorse has generated the highest cumulative return. There is lower correlation (than I expected) amongst the companies.

To understand the electric vehicle industry, I first pull daily stock return data for these companies (https://investingnews.com/daily/resource-investing/base-metals-investing/nickel-investing/top-electric-vehicle-stocks/). There are certainly other EV companies not here.

Fisker (FSR)

Greenpower (GP)

Li Auto (LI)

NIO (NIO)

NIU (NIU)

Nikola (NKLA)

ElectraMeccanica (SOLO)

Tesla (TSLA)

Workhorse (WKHS)

XPeng (XPEV)

I use the following Python function to pull adjusted close data from Yahoo. I use daily data from 1–1–2019 to 12–11–2020. Note not all companies were public at the start date.

def pull_data(tickers, startdate, enddate):

def data(ticker):

return (pdr.get_data_yahoo(ticker, start=startdate, end=enddate))

datas = map (data, tickers)

data = (pd.concat(datas, keys=tickers, names=['Ticker', 'Date']))

return data[['Adj Close']].reset_index().pivot("Date", "Ticker", "Adj Close")

Adjusted Close

I plot the adjusted close price over time for all 10 companies. From an initial glance, Tesla’s stock price has soared high above the rest.

Given the scale here, it is difficult to distinguish amongst the other companies. I include a plot for adjusted close over time but without Tesla. Nikola soared early but has since come back down. XPeng and NIO have recently separated themselves from the rest. All companies seemed to spike with each other in November recently before settling back down.

Cumulative Return

Next, I plot cumulative return over time. $1 invested in Workhorse two years ago has grown into $33. As you can see, Workhorse experienced huge returns in June 2020, and August through November 2020 were extremely volatile.

I include a plot of cumulative return without Workhorse to better visualize the other companies. $1 invested in Tesla would be worth around $10, and $1 invested in NIO would be worth around $7.

Summary Statistics (Daily Return and Volatility)

Next, I explore summary statistics on daily return data. XPeng and Workhorse have the highest average daily return while Fisker and Greenpower have the lowest. In terms of daily standard deviation, ElectraMeccanica and Workhorse are the most volatile. It is possible to annualize the daily mean and daily volatility by multiplying the results below by 365 and sqrt(252) respectively.

Next, I include correlation and covariance tables below. While these companies are all in the EV space, many pairwise correlations are not very high. Tesla’s highest correlation is with NIO (r=0.28) and its lowest is with Nikola (r=0.07). There are many companies with negative and near zero pairwise correlations.

Let me know what you would like to see next!