LONDON -- After the Easter break, we have an increase in the number of companies going ex-dividend next week. Whether you want to buy in time to be eligible for a company's dividend payment or you're looking for a bargain share price when the time has passed, you should mark your diaries.

The FTSE 100's current average dividend yield is about 3.1%, and next week's companies offer quite a spread around that. Here are three of those companies going ex-dividend in the week commencing April 8:

IMI (IMI -0.40%)
Industrial engineer IMI is set to go ex-dividend next Wednesday with respect to its final dividend of 20.7 pence per share. The payment, announced with preliminary results on March 7, takes the firm's total dividend for the year to 32.5 pence per share. That's a rise of 8% over the previous year and represents a yield of 2.5% on the current share price of 1,308 pence.

If you had bought the shares a year ago, in addition to that modest payout you would also have enjoyed a share price rise of about 30%.

GKN (GKN)
Car and plane parts maker GKN has its ex-dividend day next Wednesday, too, and again it's a final dividend. This time it's a payment of 4.8 pence per share, making up a very nice 20% rise in the full-year payment to 7.2 pence per share. That was made possible by a 19% rise in pre-tax profit for the year to December 2012.

At the current share price of 272 pence, this annual reward corresponds to a yield of 2.6% -- and just like IMI's, the shares are up about 30% over the past 12 months.

Amlin (LSE: AML)
Our third ex-dividend share for next Wednesday is insurer Amlin, which will be paying a final dividend of 16.5 pence per share. Announced on March 4, that will add to an interim dividend to provide a full-year payment of 24 pence per share. That's the smallest rise of the three, up just 4.3%, but it provides the biggest yield -- 5.6% on today's share price of 431 pence.

Amlin had a tough year in 2011 and turned in a loss of 194 million pounds, largely due to claims arising from Hurricane Sandy, but in 2012 it turned that round into a pre-tax profit of 264 million pounds.

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