And he will say the decision to pump more than $8 billion into the Reserve Bank's reserve fund, was another transparent attempt to make the deficit left by Labor after the election appear more severe. Mr Bowen will commit a Labor government to legislation to "mandate that the Parliamentary Budget Office would prepare all economic forecasts and projections that would underpin all budgets and economic statements". "This will include forecasts for all key economic parameters including inflation, unemployment, terms of trade, and nominal and real GDP," he will say, according to notes provided to Fairfax Media. Another area of specific undertaking relates to the structural budget position - whether it would be in surplus or deficit were it not for unusual or one-off factors such as a resources boom, or a war. "A Shorten Labor government will legislate for the Parliamentary Budget Office to publish an annual report on whether the budget is in structural deficit or surplus," he will pledge.

That is based on Labor's assertion that while the budget bottom line "will always fluctuate from year to year based on economic cycles, the underlying structural situation of the budget is the more important indicator". Mr Bowen will argue for a focus on structural elements claiming "the state of the bottom line which looks through annual fluctuations and cyclical events ... tells the true state of the books". "In 2013 the Parliamentary Budget Office released analysis of the structural budget balance and found that the structural budget position deteriorated sharply from 2002‐03 and actually went into structural deficit almost a decade ago towards the end of the Howard/Costello government, even though an actual deficit did not emerge during this period." The speech represents a clear attempt by Labor to wrest back the economic agenda from a government struggling to sell its own budget vision. Labor believes gains are possible because its previous problems with the politically disastrous and now defunct mining and carbon taxes, fuelled by polls putting it in front of the government, and by others showing Mr Hockey way down the list of popular ministers.

But Mr Bowen's new aggression also reflects a lesson learned by Labor in the late 1990s when the Beazley opposition failed to muscle up to John Howard by defending the achievements of the Hawke-Keating period in office. This allowed Labor's reform legacy to be all but lost as the Coalition government promulgated a version of history most advantageous to it. Finally, Mr Bowen will also call for the Parliamentary Budget Office to issue five-yearly intergenerational reports. "Of course, the PBO will be free to consult with the Treasury or any government department or agency and to collect the data it needs to fulfil this role," he will say. "But the final report will not be the property of the government of the day, rather the product of a completely independent process." He will say the shift is no reflection on the professionalism of the Treasury but a reflection of Labor's view that "transparency and rigour in budgeting need to be improved".

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