Among the anomalies in Commonwealth Bank's March quarter performance due to the inclusion of Bank of Western Australia data was surprising below-system growth in household deposits, strong growth in credit card balances and a jump in individual provisions.The bank's household deposit book increased by an annualised rate of 8.2 per cent in the March quarter, compared to system growth of 10.3 per cent for the period. Business deposits increased at an annualised rate of 2.3 per cent in the quarter, compared to system growth of 7.6 per cent.Norris said BankWest was funded by its parent HBOS and in the second half of last year funding was affected by the problems HBOS was experiencing.As a result, BankWest priced aggressively to attract deposits. When CBA took over it replaced the HBOS funding and brought BankWest's cost of funds down.Norris said balances that were above market had been rolled off and this had affected deposit balances in the quarter.CBA increased its credit card balance by an annualised rate of 2.9 per cent in the quarter. Usually the bank takes a conservative approach to its credit card business but in the March quarter its strong growth was in contrast to the contraction in the credit card books of the other big banks.Commonwealth chief financial officer David Craig said BankWest had pursued strong growth in cards and this affected the aggregate. Commonwealth Bank, ex-BankWest, had no growth in card balances over the quarter.Norris said BankWest's east coast expansion had stopped, whereas in Western Australia the business was proceeding as it had been before the acquisition.None of the branches operating on the east coast are making profits. Norris said most have been operating for just under a year and the business plan was for the branches to be profitable after 36 months.One of the biggest increases in individual provisions for the group came from BankWest. In the December half in 2008 BankWest reported individual provisions of $238 million. In its pro forma, released yesterday, CBA increased BankWest's individual provisions for the December half to $401 million. And it increased individual provisions to $443 million for the March quarter.CBA reported that "the increase in impaired assets is driven by BankWest's policy to not write off loans at 180 days past due. This is being reviewed to align to the bank's policy. These loans are provided for in the specific provisions."This detail around differences in credit card provisions appears to be the main explanation for the drastic increase in provisions, and operating loss for 2008, reported two weeks ago by BankWest for 2008.CBA has made noises about making claims against Lloyds TSB for compensation on the purchase price of BankWest, though the difference in provisioning methods can hardly have been overlooked at the time of negotiations in October last year.