July 20 (Reuters) - Westpac Banking Corp WBC.AX :
* Wbc confirms impact of apra's rwa calculation changes WBC.AX
* Actual impact on rwas will depend on the Australian mortgage portfolio size and composition as at the effective date of 1 July 2016
* Impact of change will require a further $3 billion of capital to lift group's 8.5% 31 March pro-forma cet1 capital ratio towards top end of preferred range
* The additional capital required to meet the higher rwa will contribute to the increase in capital that apra identified in the study
* In addition it increases rwa by $40.7 billion associated with the increased correlation factor
* Says increased correlation factor implies a higher expectation of more mortgages defaulting at the same time in a downturn
* "In addition it increases RWA by $40.7 billion associated with the increased correlation factor"
* The cost of holding higher capital will inevitably be borne by customers and shareholders"
* Source text for Eikon ID:nASX3FLMpz
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