Faced with declining revenue and margin contraction, Commonwealth Bank has turned its attention to cost cutting. Its aim is to capitalise on its extensive divestment program by streamlining its core businesses and shifting more of its operations to digital platforms.With a simpler operating model and "end-to-end digitisation", CBA chief executive Matt Comyn hopes to get the bank's cost to income ratio down below 40 per cent (it was 42.6 per cent in the latest half).The bank made a net profit of A$4.6 billion for the half-year, down 6 per cent from the previous corresponding period. The result includes several discontinued operations. The cash profit from continuing operations was $4.67 billion - an increase of 2 per cent over the previous corresponding period.Banking income fell 2 percent year-on-year to $11.7 billion. The net interest margin was 2.1 per cent - down from 2.14 per cent in the June half last year and 2.16 per cent in December 2017.Comyn told analysts yesterday that the sale of CBA's life insurance businesses, including CommInsure and BoComm Life, would be completed by the end of June.The completion of the CommInsure sale to AIA, which was announced in September 2017, is conditional on the transfer of its BoComm Life stake out of CommInsure. BoComm is a Chinese life insurer in which CBA has a 37.5 per cent stake. The sale of that stake to Mitsui Sumitomo Insurance is awaiting regulatory approval in China.Divestment of CBA's 80 per cent interest in Indonesian life insurer PT Commonwealth Life, which was announced last October, is also awaiting regulatory approval.The sale of other businesses, including Colonial First State Global Asset Management, is underway, while a couple of businesses, including general insurance, are still under review.The demerger of NewCo, which includes wealth management and mortgage broking business, has a target completion date of late this year.The bank will streamline its remaining businesses by integrating Bankwest into the retail banking division and small business banking into the business and private banking division.Loan application process will be automated. The bank has made an investment in the online conveyancing business PEXA and aims to incorporate automated property settlements into its business.Comyn says that 64 per cent of current investment spend is on regulatory compliance. Once that spend reduces the bank will commit more budget to automation projects.