The Rock Building Society said it expects its 2009 net profit to be in line with last year's profit of between $4.2 million and $4.4 million, the Rockhampton-based deposit-taker said in an update published through the Australian Securities Exchange.In a letter to shareholders published through the ASX, The Rock reviewed most operational aspects of the business, including a turn around in its previously declining deposit book.Thanks to the opening of a number of new mini branches and more effective marketing within central Queensland, The Rock said it expects deposit growth of 20 per cent in the financial year that ends this month.Even though the deposit book is growing The Rock reiterated that it was lending less "to match availability of funds". The Rock was previously moderately dependent on securitisation to maintain lending in the mortgage market.The Rock has recently undertaken an internal securitisation that enables it to seek funding through the Reserve Bank of Australia and the company said it was angling for $150 million in funding from the Australian Office of Financial Management.The Rock said it continued to treat its $4 million investment in a collateralised debt obligation (believed to be one of the Herald series marketed by Royal Bank of Canada in 2005) as "not impaired". The building society also owned up to cost overruns on its new core banking system that cost about $3.8 million.