Whether it's through stocks, bonds, ETFs, or other types of securities, all investors love seeing their portfolios score big returns. However, when you're an income investor, your primary focus is generating consistent cash flow from each of your liquid investments.Cash flow can come from bond interest, interest from other types of investments, and of course, dividends. A dividend is that coveted distribution of a company's earnings paid out to shareholders, and investors often view it by its dividend yield, a metric that measures the dividend as a percent of the current stock price. Many academic studies show that dividends make up large portions of long-term returns, and in many cases, dividend contributions surpass one-third of total returns.Cummins in FocusBased in Columbus, Cummins (CMI) is in the Auto-Tires-Trucks sector, and so far this year, shares have seen a price change of 2.97%. The engine maker is currently shelling out a dividend of $1.45 per share, with a dividend yield of 2.48%. This compares to the Automotive - Internal Combustion Engines industry's yield of 1.09% and the S&P 500's yield of 1.39%.In terms of dividend growth, the company's current annualized dividend of $5.80 is up 9.8% from last year. Over the last 5 years, Cummins has increased its dividend 5 times on a year-over-year basis for an average annual increase of 7.31%. Future dividend growth will depend on earnings growth as well as payout ratio, which is the proportion of a company's annual earnings per share that it pays out as a dividend. Right now, Cummins's payout ratio is 36%, which means it paid out 36% of its trailing 12-month EPS as dividend.Looking at this fiscal year, CMI expects solid earnings growth. The Zacks Consensus Estimate for 2021 is $16.37 per share, which represents a year-over-year growth rate of 36.30%.Bottom LineFrom greatly improving stock investing profits and reducing overall portfolio risk to providing tax advantages, investors like dividends for a variety of different reasons. But, not every company offers a quarterly payout.For instance, it's a rare occurrence when a tech start-up or big growth business offers their shareholders a dividend. It's more common to see larger companies with more established profits give out dividends. Income investors have to be mindful of the fact that high-yielding stocks tend to struggle during periods of rising interest rates. With that in mind, CMI is a compelling investment opportunity. Not only is it a strong dividend play, but the stock currently sits at a Zacks Rank of 3 (Hold). Zacks’ Top Picks to Cash in on Artificial Intelligence This world-changing technology is projected to generate $100S of billions by 2025. From self-driving cars to consumer data analysis, people are relying on machines more than we ever have before. Now is the time to capitalize on the 4th Industrial Revolution. Zacks’ urgent special report reveals 6 AI picks investors need to know about today.See 6 Artificial Intelligence Stocks With Extreme Upside Potential>>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Cummins Inc. (CMI): Free Stock Analysis Report To read this article on Zacks.com click here.