If you own shares in Fidia S.p.A. (BIT:FDA) then it's worth thinking about how it contributes to the volatility of your portfolio, overall. In finance, Beta is a measure of volatility. 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. Beta can be a useful tool to understand how much a stock is influenced by market risk (volatility). However, Warren Buffett said 'volatility is far from synonymous with risk' in his 2014 letter to investors. So, while useful, beta is not the only metric to consider. To use beta as an investor, you must first understand that the overall market has a beta of one. A stock with a beta greater than one is more sensitive to broader market movements than a stock with a beta of less than one.

See our latest analysis for Fidia

What we can learn from FDA's beta value

Zooming in on Fidia, we see it has a five year beta of 1.42. This is above 1, so historically its share price has been influenced by the broader volatility of the stock market. If this beta value holds true in the future, Fidia 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 Fidia fares in that regard, below.

Could FDA's size cause it to be more volatile?

Fidia is a rather small company. It has a market capitalisation of €20m, which means it is probably under the radar of most investors. It has a relatively high beta, suggesting it is fairly actively traded for a company of its size. Because it takes less capital to move the share price of a small company like this, when a stock this size is actively traded it is quite often more sensitive to market volatility than similar large companies.

What this means for you:

Since Fidia has a reasonably high beta, it's worth considering why it is so heavily influenced by broader market sentiment. For example, it might be a high growth stock or have a lot of operating leverage in its business model. This article aims to educate investors about beta values, but it's well worth looking at important company-specific fundamentals such as Fidia’s financial health and performance track record. I urge you to continue your research by taking a look at the following:

1. Future Outlook: What are well-informed industry analysts predicting for FDA’s future growth? Take a look at our free research report of analyst consensus for FDA’s outlook.

2. Past Track Record: Has FDA 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 FDA's historicals for more clarity.

3. Other Interesting Stocks: It's worth checking to see how FDA measures up against other companies on valuation. You could start with this free list of prospective options.

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.

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. Thank you for reading.