Reserve Bank of Australia deputy governor Ric Battelino suggests a low-growth future is the most likely outcome for Australian banks over the next decade.Speaking to a stockbrokers' conference in Sydney yesterday, Battelino said the banking system was "transitioning through a period of slower growth" after the global financial crisis.And he said that while history suggested credit growth would soon pick up, it would not return to the rapid growth rates that occurred in the decade to 2007/08.He predicted that Australia would see "solid economic growth, but with cautious behaviour by households and relatively low inflation". In such an economic climate, "it would be reasonable to assume that the rate of growth in credit will remain somewhere in the single-digit range."Battelino's speech provides the most detailed and confident picture yet of how the RBA expects credit growth to evolve over the next decade.The RBA said in March that banks' domestic growth opportunities were "likely to be more limited in the future", and that a return to double-digit credit growth was "unlikely". But Battelino's comments suggest the RBA is now more certain of these views.The latest comments imply that the Big Four banks will struggle to record the growth in returns of 15 per cent or more for which they are aiming.The RBA's most likely scenario, Battelino said, was that relatively heavily indebted households would continue to save at higher rates so household borrowing growth would stay low. High-growth resources businesses had been funding investment from their own earnings, he pointed out, so demand for business borrowing had stayed low.But there were signs that business credit growth was now rising again. He said that balance sheets had strengthened, investment was picking up and banks were more willing to lend.Credit advanced to the small business sector had been much more stable than that advanced to larger businesses, he noted, and had continued expanding through the global financial crisis and afterwards.Questioned after the speech about ratings downgrades for the Big Four banks' debt, Battelino expressed a "personal view" that the risks raised by the agencies "are risks that are in the past, and I think the situation's already changing."