The Reserve Bank of Australia has estimated the total value of banknotes in circulation at A$76 billion, with 93 per cent accounted for by the $50 and $100 denominations. The RBA's further analysis suggests that 15 to 35 per cent of total outstanding banknotes are used for legitimate transactions; roughly half to three-quarters are hoarded as a store of wealth or for "other purposes". RBA allocates 10 to 20 percentage points to domestic hoarding and up to 15 percentage points to international hoarding; four to eight per cent are used in the shadow economy; and five to 10 per cent are lost. The CEO of New Zealand's Co-operative Bank has called for a probe of the credit card market, telling interest.co.nz it is an area of "customer harm". The NZ Commerce Commission has just been granted market study powers, and is beginning with a review of petrol pricing. David Cunningham said credit cards should be next in line for a competition probe, describing them as "a gravy train" for banks.