Aggreko Plc (LON:AGK) is about to trade ex-dividend in the next 3 days. This means that investors who purchase shares on or after the 5th of September will not receive the dividend, which will be paid on the 1st of October.

Aggreko's next dividend payment will be UK£0.094 per share, on the back of last year when the company paid a total of UK£0.27 to shareholders. Looking at the last 12 months of distributions, Aggreko has a trailing yield of approximately 3.5% on its current stock price of £7.662. If you buy this business for its dividend, you should have an idea of whether Aggreko's dividend is reliable and sustainable. So we need to investigate whether Aggreko can afford its dividend, and if the dividend could grow.

View our latest analysis for Aggreko

Dividends are usually paid out of company profits, so if a company pays out more than it earned then its dividend is usually at greater risk of being cut. Aggreko paid out 56% of its earnings to investors last year, a normal payout level for most businesses. Yet cash flows are even more important than profits for assessing a dividend, so we need to see if the company generated enough cash to pay its distribution. Thankfully its dividend payments took up just 46% of the free cash flow it generated, which is a comfortable payout ratio.

It's positive to see that Aggreko's dividend is covered by both profits and cash flow, since this is generally a sign that the dividend is sustainable, and a lower payout ratio usually suggests a greater margin of safety before the dividend gets cut.

Click here to see the company's payout ratio, plus analyst estimates of its future dividends.

Have Earnings And Dividends Been Growing?

Businesses with shrinking earnings are tricky from a dividend perspective. If business enters a downturn and the dividend is cut, the company could see its value fall precipitously. Readers will understand then, why we're concerned to see Aggreko's earnings per share have dropped 13% a year over the past five years. When earnings per share fall, the maximum amount of dividends that can be paid also falls.

Many investors will assess a company's dividend performance by evaluating how much the dividend payments have changed over time. Aggreko has delivered an average of 9.5% per year annual increase in its dividend, based on the past 10 years of dividend payments. Growing the dividend payout ratio while earnings are declining can deliver nice returns for a while, but it's always worth checking for when the company can't increase the payout ratio any more - because then the music stops.