5 FTSE 100 Dates For Your April Diaries

April will start off quite slowly for company news, but things will pick up around the middle of the month. There will be updates from a good few FTSE 100 companies, and we'll keep you updated on them as the month progresses. But in advance, here are five of the most important diary dates:

Thursday 11 April, Marks & Spencer

Marks & Spencer (LSE: MKS) will be bringing us a fourth-quarter update on the 11th, shedding light on how the year to 31 March has gone -- full results will be with us on 21 May. The share price got a bit of a boost last week, to 395p, on rumours of an £8bn bid in the offing from the Qatari Investment Authority, but other than that the shares have had a pretty lamentable few years.

Forecasts suggest a 7% drop in earnings per share, putting the shares on a price-to-earnings (P/E) ratio of 12, with a nearly twice-covered dividend yield of 4.3%. With modest earnings and dividend rises pencilled in for 2014 and 2015, the P/E would fall to 11 and 10.5 respectively, with the yield rising to 4.5% and 4.8%.

Wednesday 17 April, Tesco

Full-year results from Tesco (LSE: TSCO) are due on the 17th, after what has been quite a tumultuous year. The share price famously slumped in January 2012 after the UK's biggest supermarket reported a weak Christmas trading period. But since around October, the price has been steadily rising, reaching 373p at the time of writing.

And this time, things looked better over Christmas and New Year, with UK like-for-like sales up 1.8%, and the company reported "recovering in-store performance". Forecasts for the year to 28 February put the shares on a P/E of 12, with a 4% dividend yield.

Wednesday 24 April, GlaxoSmithKline

It's time for first-quarter figures from GlaxoSmithKline (LSE: GSK) on the 24th. The pharmaceuticals giant reported flat earnings for the year to December 2012, but lifted its total dividend by 5.7% to 74p per share, for a yield of 5.5%. At the time, chief executive Sir Andrew Witty told us the firm expects 3-4% growth in core earnings per share for 2013, along with "further strong cash generation", which should support increasing dividends.

Analysts are forecasting a 5.4% boost to this year's annual payment, which would provide a yield of 5.2% on the current share price of 1,506p -- and that's significantly above the average FTSE 100 dividend of around 3.1%.

Wednesday 24 April, Barclays

Barclays (LSE: BARC) will also deliver first-quarter results the same day, following on from a strong performance in 2012 when the high-street bank reported a 24% rise in earnings per share and the fourth annual dividend rise in a row. After the 2009 payment was slashed to just 2.5p per share, it has crept back to 6.5p last year, with around 7.25p currently forecast for 2013. With the shares currently changing hands for 287p, that would be a yield of 2.5%.

And that 287p share price is 90% up since last July's low (and it has been even higher, exceeding 320p in February), but even after that, the shares are still on a forward P/E of under 8.

Tuesday 30 April, BP

It's the turn of BP (LSE: BP) to deliver first-quarter figures on the last day of the month, and a lot of people will be eyeing up the oil giant's cash situation. After disposing of assets over the past couple of years to help meet the costs of the Gulf of Mexico disaster, BP announced last week that it is to embark on a share buyback programme worth up to $8bn. That amount represents the cost of its original 50% stake in TNK-BP, which it has just sold to Russian state oil company Rosneft for $12.5bn.

The shares have not moved much over the past couple of years, standing at 463p as I write, and are currently on a P/E of just 8.2 based on forecasts for the 2013 full year.

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