Labor has bowed to pressure from Treasurer Joe Hockey and released economic modelling showing the budget burden "falls most heavily" on low and middle income families with children.
The modelling, conducted by the National Centre for Social and Economic Modelling, sparked a furious political debate on Monday when the government cast doubt on the findings and demanded it be released in full.
The data was commissioned by the Labor Party. Its preliminary release found poorer families would be most affected by the Abbott government's second budget.
"The results clearly demonstrate that low income families with children are the main family group to be adversely impacted by policy changes since the last election," the report notes.
"High income families and singles and couples without children are shown to be largely unaffected by this budget either in the short or longer term".
The NATSEM modelling also found that under current budget measures, low income families will experience a much larger loss of disposable income while some higher income families will see a slight increase in 2018 and 2019.
The 13-page report cautions the analysis only measures the impact of the budget's major "hip-pocket" measures and does not evaluate the "totality of the budget reforms". Measures analysed include reductions to Family Tax Benefit B and an increased petrol tax, which are outstanding measures from last year's budget.
Labor's finance spokesman, Tony Burke, said the data contained one simple message: "A $6000 hit for a typical family, by this government in this budget."
Mr Hockey on Monday took the remarkable step of attacking Labor leader Bill Shorten's press secretary over the modelling, which was only partially released to the media on Sunday.
Later, during an appearance on Q&A, Mr Hockey said he wanted to see the assumptions NATSEM used before commenting on the findings.
"It's like a sausage machine ... I want to see what goes in that sausage machine," he said.
