'Big Four' banks downgraded
THE revisions by Standard and Poor's come as ratings agencies tighten their definition of risk after the collapse of Lehman Brothers more than three years ago.
Earlier this week, Standard & Poor's cut the ratings of 15 banks in Europe and the United States due to the revised criteria.
These downgrades had been flagged but it is more evidence that banks are operating in a very risky and uncertain world.
Westpac, the Commonwealth Bank, ANZ and NAB now have the fourth highest rating on the S&P scale.
Even so, the big four remain among a handful of highly rated banks in the world, and S&P made the point that Australian banks are bolstered by conservative regulation and the banking sector's low risk appetite.
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