The Australian sharemarket has gained more than 1 per cent to its highest level in five months as the local earnings season kicked off strongly and bank stocks climbed. The big four banks led the gains, with National Australia Bank up 2.4 per cent, Westpac and ANZ both rising 1.9 per cent, and Australia’s biggest bank, CBA, climbing 1.8 per cent. The lenders are among the companies due to report earnings in the next week or so. In the earnings results space, financial services provider Credit Corp’s shares slumped despite posting a 12 per cent rise in profits. Bendigo Bank shares rose 0.7 per cent after the bank announced that ex-HSBC UK executive Christopher Dean will join the bank as chief customer officer in September.