With the stock market being highly volatile and investors nervous at the present time, buying stocks with excellent track records of earnings growth could be a sound move. After all, robust earnings may command a premium valuation moving forward.

One company that has increased its bottom line at a double-digit rate in each of the last five years is easyJet (LSE: EZJ). Its trading update released today showed that it has made encouraging progress in the first quarter of the financial year, despite challenging operating conditions caused by the terror attacks in Egypt and France. As a result of these events, revenue per seat and total revenue dropped compared to the previous year.

However, easyJet’s load factor increased by 0.6% to 90.3% and bookings for the second quarter are showing a marked improvement on the relatively disappointing performance in November and December (the months following the terrorist attacks). And with total passengers continuing to rise (by 8.1% versus the previous year) and easyJet being on target to meet full-year expectations, it remains a relatively appealing buy at the present time. That view is further enhanced by easyJet’s valuation, with a price-to-earnings growth (PEG) ratio of 1.5 indicating that it offers upside potential.

Growth ahead

Also having a strong track record of earnings growth is technology company ARM (LSE: ARM). It has increased its earnings in four of the last five years and during that time, its bottom line has more than doubled.

Looking ahead, ARM is expected to post a rise in net profit of 69% for the 2015 financial year and with growth of 14% being pencilled-in for 2016, it remains a very appealing growth play. It’s undoubtedly becoming a more mature business and is expected to raise dividends per share by 22% this year, which indicates that in the coming years it may become an increasingly attractive dividend play.

With ARM’s business model being focused on intellectual property rather than manufacturing, it has the potential to lead the growth in new technology rather than play catch-up. This should ensure that margins and profitability remain robust and that ARM offers a relatively reliable income stream for its investors in the long run.

Defensive appeal

Meanwhile, National Grid (LSE: NG) continues to be a hugely enticing defensive play. It may be unable to compete with the likes of easyJet and ARM when it comes to earnings growth prospects, but it offers a yield of 4.8% as well as a highly robust earnings stream. With markets being exceptionally volatile at the present time, demand for both of these assets could rise as we move through 2016.

Furthermore, National Grid continues to trade on a relatively appealing valuation despite its share price having outperformed the FTSE 100 by 16% in the last year. For example, it has a price-to-earnings (P/E) ratio of 15.4. Given its robust outlook, this indicates that further share price gains are on the cards.

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Peter Stephens owns shares of ARM Holdings, easyJet, and National Grid. The Motley Fool UK has recommended ARM Holdings. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.