Bank of Western Australia's problem loans worsened over the June 2009 quarter, and by a greater degree than for any other bank whose quarterly "pillar 3" report this newsletter's revised so far.BankWest reported that impaired loans increased by $471 million to $1.37 billion over the June quarter. Loans 90 days or more past due increased. The increasing strife was, unsurprisingly, contained within its corporate book, where problem loans increased by around $500 million to $1.26 billion.