Investec Bank Australia has returned to profitability. As a result of a significant decline in impairments, the Australian operation contributed £3.4 million to group earnings for the year to March 2013.A financial report issued by the group on Friday shows that impairments in the Australian operation were £50 million lower than the previous year, falling from £67.8 million in 2011/12 to £17.8 million in 2012/13.There were few details about the performance of the business in Australia. However, the results' presentation said the professional finance franchise continued to perform well. It also said the business had benefited from strong growth in fees earned in corporate advisory, and in corporate and specialised lending.Operating income was £132.7 million - an increase of 30.4 per cent over the previous year. Operating profit was £3.4 million - a turnaround from a loss of £65.8 million in 2011/12.Investec Bank Australia reported a loss of A$71.6 million last year, after clearing out the bulk of its non-performing property development book.