Long-term income investors know that yield isn't everything when it comes to dividend stocks. Steadily rising payouts pay off down the road, too.

Not only do rising dividends lift the yield on an investor's original cost basis, they're indicative of a firm's ability to withstand the economy's - and the market's - inevitable ups and downs.

"Dividend growers tend to be quality franchises built to weather diverse market environments," BlackRock portfolio manager Tony DeSpirito and now-retired BlackRock PM Robert Shearer wrote in a 2015 report. "If you think about it, these are generally high-quality businesses with ample free cash flow, and that's precisely what's needed to grow the dividend. So you have a very attractive combination of quality franchises, solid balance sheets and positive trends in cash flow and earnings."

The Dividend Aristocrats are companies in Standard & Poor's 500-stock index that have raised their payouts every year for at least 25 consecutive years. They are a host of household names that offer size, longevity and familiarity, providing comfort amid market uncertainty.

Here are the current 57 Dividend Aristocrats - including several new faces that were just added in January 2019. These have been among the best dividend stocks for income growth over the past few decades, and they're a great place to start if you're looking to add new dividend holdings to your long-term portfolios.

Roper Technologies

Roper Technologies (ROP, $299.76) - an industrial company whose businesses include medical and scientific imaging, RF technology and software, and energy systems and controls, among others - was added to the Dividend Aristocrats in 2018. The diversified industrial company was tapped for the honor after it hiked its dividend for a 25th straight year at the end of 2017. Then in November 2018, ROP hiked its dividend for a 26th consecutive year, this time by 12% to $1.85 a share on an annual basis.

With a payout ratio of just 15.2%, Roper should have ample room to keep the dividend hikes coming for many years to come.

Sherwin-Williams

Sherwin-Williams (SHW, $420.87) is one of the largest paints, coatings and home-improvement companies in the world, thanks to its $11 billion acquisition of Valspar in 2017. The company's global reach has actually hindered performance lately, however. Fourth-quarter results fell short of Wall Street's expectations, hurt by sluggishness overseas.

But longer-term, analysts expect better-than-average profit growth. Analysts polled by Refinitiv expect earnings to grow at an average annual rate of almost 17% for the next five years.

"While the current macroeconomic outlook is less than clear, we see significant opportunities for profitable growth throughout the business," management said in a news release.

And it's not like income investors need to worry about Sherwin-Williams' steady and rising dividend stream. The company has hiked its distribution every year since 1979. SHW pays out just 29% of its earnings as dividends, vs. 40% for the S&P 500, so the company has ample resources to keep the streak alive.

Cintas

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Cintas (CTAS, $191.55) is perhaps best-known for providing corporate uniforms, but the company also offers maintenance supplies, tile and carpet cleaning services and even compliance training. As such, it's seen by some investors as a bet on jobs growth.

There may be something to that. Shares have more than tripled over the past five years vs. a gain of just 51% for the S&P 500. In January, the economy notched its 100th consecutive month of employment gains. Meanwhile, weekly jobless claims stand at levels last seen in 1969.

Regardless of how the labor market is doing, Cintas is a stalwart as a dividend payer. The company has raised its payout every year since going public in 1983. Most recently, in October, Cintas raised its annual dividend by 26.5% to $2.05 a share.

Ecolab

Ecolab (ECL, $159.14) provides water treatment and other industrial-scale maintenance services for several industries, including food, healthcare, and oil and gas. Ecolab's fortunes can wane as industrial needs fluctuate, though; for instance, when energy companies pare spending.

Over the long haul, though, ECL shares are a proven winner. Over the past decade, the stock has delivered an annualized return, including dividends, of 18%, vs. just 12% for the S&P 500. That's thanks in