Dividend investors would be wise to focus not just on a stock's current yield, but also on the long-term growth potential of its dividends. That's because strong businesses that consistently raise their dividend payouts reward shareholders with a steadily rising income stream that essentially equates to a raise every year. And well, who doesn't like a raise?

But there are other reasons to value dividend growth so highly, and they're well supported by research. For instance, a study by C. Thomas Howard published in Advisor Perspectives found that for every percentage point a stock's yield rises, its annual return increases by 0.22 percentage points if it's a large cap, 0.25 if it's a mid cap, and 0.46 if it's a small cap. Even better, Howard found that dividend-growing stocks outperformed dividend cutters by 10 percentage points per year from 1973 to 2010 and beat both flat- and no-dividend stocks. And the icing on the cake is that Howard showed that this outperformance came with a third less volatility. Higher returns, less volatility-induced stress, and a steadily growing income stream -- what's not to love?

With that in mind, here are five stocks that have grown their dividends by more than 30% over the past year.


1-Year Dividend Growth Rate

National Oilwell Varco (NYSE:NOV)


Texas Instruments (NASDAQ:TXN)


CVS Caremark (NYSE:CVS)


Western Union (NYSE:WU)


UnitedHealth Group (NYSE:UNH)


Source: S&P Capital IQ.

National Oilwell Varco is a global titan in the oil and gas services industry. It provides many types of equipment and components used in oil and gas drilling and production operations, from complex deepwater drilling rigs to small spare parts. Workers in its industry say there's "No Other Vendor," and CAPS participants have awarded National Oilwell Varco with the highest five-star rating. Its stock is currently yielding a growing 1.4%.

Texas Instruments designs and manufactures semiconductors. Its diversified product lineup includes data converters, digital signal processors, microcontrollers, applications processors, and calculators, among many other items. Texas Instruments currently has a four-star ranking on CAPS and offers investors a 2.9% yield.

CVS Caremark operates more than 7,000 drugstores across the United States. It also offers pharmacy benefit management services to employers, unions, government groups, and other sponsors of health benefit plans. Fools have given CVS Caremark a four-star rating in CAPS, and its stock is yielding 1.5%.

Western Union offers money movement and payment services, providing people and businesses with fast, reliable, and convenient ways to send money around the world. Western Union currently sports a four-star rating in CAPS and is yielding 2.7%.

Health-insurance giant UnitedHealth Group provides consumer-oriented health-benefit plans and services through a network of 780,000 physicians and 5,900 hospitals. UnitedHealth Group has a four-star CAPS rating and offers investors a fast-growing 1.6% dividend.

The Foolish bottom line
Had you invested in these companies a year ago, you would have enjoyed total dividend increases ranging from 31% to 36%. That level of growth would provide a substantial boost to just about any investor's dividend income. But more important to investors today is to identify the companies that will grow their dividends substantially in the years ahead. If you're interested in hearing about some excellent companies that are likely to boost their dividends from this point forward, I'd like to offer you a brand-new free report from The Motley Fool's expert analysts called "Secure Your Future With 9 Rock-Solid Dividend Stocks." Today I invite you to download it at no cost to you. To discover the identities of these companies before the rest of the market catches on, you can access this valuable free report by simply clicking here now.