Treasurer Scott Morrison has stressed his first budget is "not typical", but he has kept one infamous tradition: buried deep within the documents are the keys to eight weeks of so-called election announceables.
The government has booked $1.6 billion in expenses for "decisions taken but not yet announced" over the next three years, including $476.5 million in the coming 2016-17 financial year.
By the same token, unannounced decisions on the revenue side of the budget will reduce tax receipts by $425 million over four years.
However, the government has also projected almost $2 billion in unannounced savings for 2019-20, the final year covered by this budget. That will allow it to argue that any election commitments are fully funded, and not irresponsible spending.
Finance Minister Mathias Cormann on Wednesday confirmed the stash of cash but noted it was a feature of every budget.
"Obviously, there is always a range of decisions where still a bit more work needs to be done before they're ready for public announcement," he told Channel Seven. "But by the time we get to the pre-election economic and fiscal outlook, all of that information will be publicly revealed."
Opposition finance spokeswoman Penny Wong speculated the unannounced savings measures would mean cuts down the track. "There must be some nasties in it," she said. "Maybe they're saving it up for the last week to try and hide it from everybody."
Commentators have often seen the unannounced decisions provision as a "war chest" for governments facing an election. In 2010, the Labor government's budget, delivered under Kevin Rudd, allowed for almost $1.3 billion in unannounced measures over four years, months ahead of the election, under Julia Gillard, as it transpired.
However, the parliamentary library has tracked the controversial line item over 12 budgets and concluded it was not habitually abused by governments in election years.
The "decisions taken but not yet announced" item is not the only pool of money the government has at its disposal. It can also dip into the contingency reserve, which includes money for unforeseen circumstances, commercial-in-confidence matters and unannounced policies.
The reserve has been drawn down by a billion dollars in 2016-17. However, one expenditure item definitely booked against it is $160 million for the promised plebiscite on same-sex marriage. Fairfax Media understands it will be announced in the pre-election fiscal outlook (PEFO), which is due within 10 days of the writs being issued for an election.
The $160 million figure is essentially the $158.4 million the Australian Electoral Commission estimated to be the cost of holding the plebiscite outside of a general election. It suggests there will be very little, if any, public funding for either the "yes" or "no" campaigns - although the Attorney General's office would not confirm either way.
Another $160 million has also been put aside in the contingency reserve for the referendum on constitutional recognition of Indigenous Australians.
Prime Minister Malcolm Turnbull is expected to call an election either Friday or this weekend, to be held on July 2.
