It looks like Ashtead Group plc (LON:AHT) is about to go ex-dividend in the next three days. You will need to purchase shares before the 13th of August to receive the dividend, which will be paid on the 11th of September.

Ashtead Group's next dividend payment will be UK£0.34 per share. Last year, in total, the company distributed UK£0.41 to shareholders. Calculating the last year's worth of payments shows that Ashtead Group has a trailing yield of 1.6% on the current share price of £26.14494. Dividends are an important source of income to many shareholders, but the health of the business is crucial to maintaining those dividends. So we need to check whether the dividend payments are covered, and if earnings are growing.

View our latest analysis for Ashtead Group

If a company pays out more in dividends than it earned, then the dividend might become unsustainable - hardly an ideal situation. Ashtead Group paid out a comfortable 25% of its profit last year. That said, even highly profitable companies sometimes might not generate enough cash to pay the dividend, which is why we should always check if the dividend is covered by cash flow. Luckily it paid out just 24% of its free cash flow last year.

It's encouraging to see that the dividend is covered by both profit and cash flow. This generally suggests the dividend is sustainable, as long as earnings don't drop precipitously.

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

Have Earnings And Dividends Been Growing?

Businesses with strong growth prospects usually make the best dividend payers, because it's easier to grow dividends when earnings per share are improving. Investors love dividends, so if earnings fall and the dividend is reduced, expect a stock to be sold off heavily at the same time. That's why it's comforting to see Ashtead Group's earnings have been skyrocketing, up 22% per annum for the past five years. Earnings per share have been growing very quickly, and the company is paying out a relatively low percentage of its profit and cash flow. This is a very favourable combination that can often lead to the dividend multiplying over the long term, if earnings grow and the company pays out a higher percentage of its earnings.

Another key way to measure a company's dividend prospects is by measuring its historical rate of dividend growth. Ashtead Group has delivered an average of 30% per year annual increase in its dividend, based on the past 10 years of dividend payments. It's great to see earnings per share growing rapidly over several years, and dividends per share growing right along with it.