Anyone researching Aeris Environmental Ltd (ASX:AEI) might want to consider the historical volatility of the share price. Volatility is considered to be a measure of risk in modern finance theory. Investors may think of volatility as falling into two main categories. The first type is company specific volatility. Investors use diversification across uncorrelated stocks to reduce this kind of price volatility across the portfolio. The other type, which cannot be diversified away, is the volatility of the entire market. Every stock in the market is exposed to this volatility, which is linked to the fact that stocks prices are correlated in an efficient market.

Some stocks mimic the volatility of the market quite closely, while others demonstrate muted, exagerrated or uncorrelated price movements. Some investors use beta as a measure of how much a certain stock is impacted by market risk (volatility). While we should keep in mind that Warren Buffett has cautioned that 'Volatility is far from synonymous with risk', beta is still a useful factor to consider. To make good use of it you must first know that the beta of the overall market is one. Any stock with a beta of greater than one is considered more volatile than the market, while those with a beta below one are either less volatile or poorly correlated with the market.

View our latest analysis for Aeris Environmental

What AEI's beta value tells investors

Looking at the last five years, Aeris Environmental has a beta of 1.42. The fact that this is well above 1 indicates that its share price movements have shown sensitivity to overall market volatility. If this beta value holds true in the future, Aeris Environmental shares are likely to rise more than the market when the market is going up, but fall faster when the market is going down. Share price volatility is well worth considering, but most long term investors consider the history of revenue and earnings growth to be more important. Take a look at how Aeris Environmental fares in that regard, below.

Does AEI's size influence the expected beta?

Aeris Environmental is a rather small company. It has a market capitalisation of AU$70m, which means it is probably under the radar of most investors. Relatively few investors can influence the price of a smaller company, compared to a large company. This could explain the high beta value, in this case.

What this means for you:

Since Aeris Environmental tends to moves up when the market is going up, and down when it's going down, potential investors may wish to reflect on the overall market, when considering the stock. This article aims to educate investors about beta values, but it's well worth looking at important company-specific fundamentals such as Aeris Environmental’s financial health and performance track record. I urge you to continue your research by taking a look at the following:

1. Past Track Record: Has AEI been consistently performing well irrespective of the ups and downs in the market? Go into more detail in the past performance analysis and take a look at the free visual representations of AEI's historicals for more clarity.

2. Other High-Performing Stocks: Are there other stocks that provide better prospects with proven track records? Explore our free list of these great stocks here.

If you spot an error that warrants correction, please contact the editor at editorial-team@simplywallst.com. This article by Simply Wall St is general in nature. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. Simply Wall St has no position in the stocks mentioned.

We aim to bring you long-term focused research analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Thank you for reading.