Principal Financial Group reported second-quarter net income of $456.6 million, a 48 percent increase from $309.5 million reported for second-quarter 2017. Net income per diluted share was $1.58 for second quarter 2018, compared with $1.06 in the prior-year quarter. The Des Moines-based financial services company said it benefited from a $99.5 million after-tax gain related to a sale of an equity method investment. Principal’s board authorized a 53-cent-per-share common stock dividend for the third quarter, payable on Sept. 28. Principal returned over $670 million to shareholders in the first half of the year through common stock dividends and share repurchases, said Dan Houston, chairman, president and CEO. Principal has also committed $130 million to strategic acquisitions, among them its recent purchase of fintech firm RobustWealth, which Houston called “an important step forward for Principal as we look to make investment advice more accessible to customers.”