It's not just Australia. I looked it up some time ago after a friend (a COBOL programmer) said it was still being used a lot, I didn't believe him at first but apparently there's a lot of COBOL code out there. "Billions and billions" of lines as Sagan would say
I always have to think of the Dijkstra quote: "The use of COBOL cripples the mind; its teaching should, therefore, be regarded as a criminal offense.".