The FTSE 100 has lost 11% of its value over the past 12 months, and at 6,186 points as I write it’s only managed a rise of 4% over the past five years. Granted there have been dividends averaging around 3% over the period and that’s enough to keep shares ahead of money in a savings account. But that very poor performance has surely left us with some terrific bargains.

When you see a company that was struggling and had to cut its over-stretched dividend, but then went on to turn itself around and strengthen its balance sheet in impressive fashion, while building its dividends up again to yield 4% last year, you might think investors would be keen to buy the shares.

Well, that’s what insurer Aviva (LSE: AV) has been through. But no, its shares have fallen 20% over the past 12 months, to 424p, and are now on a forward P/E of just nine based on forecasts for 2016, dropping to only around 8.3 should 2017 forecasts prove accurate. And that dividend? There’s a further recovery on the cards this year, with the City’s analysts suggesting a yield of 5.6% and growing to 6.3% on 2017 forecasts.

What might convince the sceptics and get Aviva shares heading back upwards? I think it’s going to take an actual sustained earnings recovery rather than just forecasts, but if interim results due in August show that a forecast doubling of EPS is realistic, that’s when we might see some movement.

Very cheap bank

Barclays (LSE: BARC) shares took a tumble when the bank announced it was to slash its 2016 dividend by more than half, and at 165p they’re down 36% over 12 months. Many saw the move as an unexpected disaster, but the timing makes it seem anything but to me. New boss Jes Staley has been in charge only since December, and that makes it much easier for him to take more drastic action than an incumbent boss and not be seen as the bad guy… it’s other people’s mistakes he’s fixing, not his own.

Dividends are only going to provide yields of around 2% this year and next (and if Barclays shares should recover any of their lost ground during that time, the yield would drop even lower). At a time when other banks, like Lloyds Banking Group, are ramping up their dividends, a lot of income investors will have deserted Barclays.

But that’s put Barclays shares on a P/E of 7.3 based on 2017 forecasts, and that seems almost criminally cheap to me. Those who buy now could do very nicely over the next few years, although it might take a restart to the firm’s dividend rises to get investors back on board.

Oil recovery

Finally, if now isn’t the time to buy BP (LSE: BP) shares, I don’t know when will be. The price of oil is slowly coming back, and at $48 a barrel as I write it’s closing in on the $50 level and is more then 50% up from its low point in January. But BP shares have gained only 4% so far in 2016, to 367p, and are down 21% over 12 months.

BP has said all along that it expected cheap oil to last several years, and has made it clear that it really isn’t too worried about it. The company is in a sound enough financial shape without the debt problems that some smaller firms face, and has made a point of maintaining its dividend — we’re expecting a 7.4% yield this year!

What would set BP shares back on an upward path? Simple, I think, just a rising oil price. How long it takes is still anybody’s guess, but every dollar over 50 could gear up nicely for the future of BP shares.

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Alan Oscroft owns shares of Aviva and Lloyds Banking Group. The Motley Fool UK has recommended Barclays and BP. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.