2016 has been an excellent year so far for Tullow Oil (LSE: TLW), with the Africa-focused oil producer posting a rise in its share price of 55%. As a result of this, many investors may feel that Tullow is due for a less impressive period, with the potential for profit taking. And with the price of oil still likely to be volatile and having a good chance of falling in the short run, Tullow’s share price could come under pressure and fall by 20%.

However, in the long run Tullow’s shares appear to offer much more upside than downside. That’s because of the company’s production guidance, with Tullow’s new Project TEN in Ghana set to come on-stream within a matter of months and significantly boost production. This has the potential to cause a step-change in Tullow’s profitability, with its pre-tax profit forecast to rise from £58m in the current year to £208m next year. This puts Tullow on a price-to-earnings-growth (PEG) ratio of only 0.1, which indicates that while a 20% fall in its share price can’t be ruled out, Tullow offers stunning capital gain potential.

Buy for the long term

Also enduring a tough period in recent years has been support services company Balfour Beatty (LSE: BBY). It has been lossmaking in each of the last three years and its share price has declined by 28% during the last five years as a result.

Looking ahead, Balfour Beatty is forecast to return to profitability in the current year, gradually exiting unfavourable contracts and winning much more lucrative new ones. And with its bottom line forecast to rise by 61% next year, investor sentiment could begin to improve as the market prices-in better financial performance.

Although Balfour Beatty is a relatively risky play and there are no guarantees that its shares will rise in the near term, its PEG ratio of 0.2 indicates that it offers a wide margin of safety. Therefore, it seems to be a worthy long-term buy, although it’s likely to be somewhat volatile in the short-to-medium term.

Brexit fears

Meanwhile, Land Securities (LSE: LAND) has seen its share price fall by 3% since the turn of the year as fears surrounding a Brexit begin to dominate investors’ thoughts. While a Brexit would be likely to cause a significant fall in Land Securities’ share price, the risk/reward ratio on offer seems to be relatively appealing. That’s because Land Securities trades on a price-to-book (P/B) ratio of only 0.85, which indicates that it has a generous margin of safety and that its shares could beat the market over the medium-to-long term.

In addition, Land Securities remains a relatively appealing income play. It currently yields 3.1% and with dividends having risen by 3.8% per annum during the last five years and being covered 1.3 times by profit, there seems to be a good chance that they’ll beat inflation over the medium-to-long term.

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Peter Stephens owns shares of Land Securities Group. The Motley Fool UK has no position in any of the shares mentioned. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.