Indian Bank, a century-old state-owned lender based in the country’s south, has emerged as Asia’s top-performing bank stock in the past year, driven by a focus on consumer loans that are less likely to sour than corporate advances. The Chennai-based firm is aiming to boost retail lending, which includes mortgages and loans underpinned by gold as collateral, to account for 60 percent of its loan book over the next two years, up from 52 percent at the end of December, according to Chief Executive Officer Mahesh Kumar Jain.