They were a relatively large share of global bank debt-funding in that year, but that as much reflected the decrease in the number of highly rated institutions, as well as a lack of borrowing by other banks around the world through that period, as it did a pick-up in borrowing by the Australian banks.
(That is, it was as much a function of the denominator shrinking as the numerator growing.) The Australian banks are a much smaller share of the  7  Debelle G (2011), “The Australian Bond Market in 2011 and Beyond”, KangaNews Australian DCM Summit, Sydney, 15 March.