LONDON -- The FTSE 100 (INDEX: ^FTSE), at current levels of around 5,500 points, is on a trailing dividend yield of 3.9%. That's really a pretty decent return, even if the index itself is only going sideways. So it makes a lot of sense to invest in high-yielding shares while the indexes are depressed, and take the annual payouts while patiently awaiting the recovery that will surely come.

With that in mind, here's a quick look at three companies from the various FTSE indexes that have lifted their dividends this week...

Centrica
Centrica
(LSE: CNA.L) raised its interim dividend by 8% to 4.62 pence today, on the release of its first-half results, in line with its practice of paying 30% of the previous year's dividend. Forecasts suggest a full-year dividend yield of 5.2% based on the current share price of 314 pence.

Revenues for the six months to June 30 were up 4% to 12 billion pounds, with adjusted pre-tax profit coming in 14% up, at 767 million pounds.

Long-term income investors have done well with Centrica -- its payout has grown by a cumulative 55% since 2006.

ITV
Broadcaster and TV producer ITV (LSE: ITV.L) reported an 11% rise in revenues to 1.28 billion pounds from its first-half trading, and doubled its first-half dividend to 0.8 pence per share from 0.4 pence last year. Adjusted pre-tax profit was recorded at 235 million pounds, up 15%, with adjusted earnings per share up by a similar margin to 4.7 pence.

Although advertising revenues are under increasing pressure -- the BBC's Olympics coverage won't help -- the firm's production division, ITV Studios, enjoyed a 34% rise in revenues.

Full-year dividend yield is forecast at 3.1% based on a 77 pence share price, but ITV's forecast year-end price-to-earnings ratio stands at an undemanding 8.7, so there's room for recovery there too.

Travis Perkins
Building materials supplier Travis Perkins (LSE: TPK.L) told us that interim profits were impacted by the extensive rain we've had so far this summer, reckoning that it knocked around 10 million pounds off profits. Overall revenues were up 2.7% to 2.41 billion pounds, though like-for-like revenues fell by 0.7%.

Adjusted pre-tax profit fell modestly, by 1.9% to 138 million pounds, but the firm was still able to boost its interim dividend by a juicy 23% to 8 pence per share, and it's well covered by 57.3 pence in earnings. The full-year dividend forecast is modest at 2.4%, but the shares have done well since the beginning of the year.

An honorable mention
I must give a tip of the hat to SSE (LSE: SSE.L) today, after the multi-utility's first-quarter management statement outlined its dividend policy. While not giving us any hard numbers, the firm stressed its aim of providing dividend increases of 2% more than retail price inflation. With the shares at 1,306 pence, current forecasts put the March 2013 yield at 6%.

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