Around seven per cent of National Australia Bank's SME loans are "refinanced to or from other institutions", the bank said in written answers supplied to the Standing Committee on Economics and published last week.NAB also said that "approximately 16 per cent of home lending was customers who refinanced their mortgage from other institutions to NAB."Only half this proportion shop around on credit card deals.Around "eight per cent of credit card accounts moved to a lower rate credit card or personal loan; both within NAB and other institutions," the bank said. These fragments of data were in answers from NAB, following up evidence by its CEO, Andrew Thorburn, to the House of Representatives committee last month.The committee late last week published more than 100 responses from Thorburn and other big bank CEOs on matters placed on notice, or avoided, during the hearings.