Australia: Why is child care so expensive?

"It's draconian. It's outrageous," says Gwendolyn Hyslop as she goes through the calculations in her household budget.
Dr Hyslop is a sole parent to two preschool children who spends more than half her take-home salary on child care.
An academic linguist at the University of Sydney, she lives in the Blue Mountains. The four-hour daily commute is a small price to pay.
When living closer to campus, she spent more than 80 per cent of her pay cheque on child care. Now she's considering taking out a loan "to afford to continue working".