It is widely believed or assumed that the Medicare levy fully funds Medicare. This has never been the case since Medicare started. All Australian Commonwealth governments since 1983 have been reluctant to clearly explain this to the public, for reasons that are not clear.
It is important to note that Medicare represents only a small proportion of the total spending on health care of $140 billion (as quoted below) in Australia, and in particular that Australians spent more out of pocket for their health services ($24.8 billion, as quoted below) than the total amount allocated to Medicare ($19 billion, quoted above).
"The Australian Institute of Health and Welfare (AIHW) calculates that spending on all health care in Australia in 2011-12 totalled just over $140.0 billion or 9.5% of gross domestic product (GDP). This is around $5,881 in recurrent expenditure per person (not including capital). Most health spending in Australia (almost 70%) is funded by governments, with the largest component ($42.0 billion) for the provision of public hospital services. (…) Individuals contributed around $24.8 billion out-of-pocket on purchasing health services, which on a per capita basis is around $1,101." https://www.aph.gov.au/About_Parliament/Parliamentary_Departments/Parliamentary_Library/pubs/rp/rp1314/QG/HealthAust