These dividend ‘kings’ have had average annual returns of up to 21% for 25 years By: MarketWatch May 26, 2016 at 13:15 PM EDT Eighteen U.S. companies have increased their dividends for at least half a century, writes Phil van Doorn. Read More >> Related Stocks: 3M Co American States Water Company Cincinnati Financial Coca-Cola Company Colgate-Palmolive Dover Corp Emerson Electric Farmers & Merchants Bancorp Genuine Parts Hormel Foods Johnson & Johnson Lancaster Colony Cor Lowe's Companies Nordson Corp Northwest Natural Gas Company Parker-Hannifin Procter & Gamble Standard & Poors 500 Vectren Corp