No, Scott Morrison is not promising average Australians significant tax cuts. To use a technical term, the proposed cuts are bugger all.The Treasurer is promising a radical flattening of the tax scale to primarily benefit the top tier of income earners.

Average total earnings for employees is running at about $62,000 a year.Mr Morrison is promising such people a tax cut of $540 next financial year although it wont reach their pockets until August 2019.

Allowing for generous wages growth of 3.25 per cent a year, that $62,000 would turn into $77,600 in seven years time when the final leg of Mr Morrisons radical plan kicks in. By 2024-25, that person on average total earnings would still only be getting next years $540 cut.

By comparison, someone on $200,000 in 2024-25 would receive a $7225 tax cut.

The figures are there for all to play with on the very front page of the Treasurys budget site an income tax calculator that spells out exactly what you will or wont receive.

The above calculations err on the conservative side. Median incomes the people in the middle of the range of earnings are lower than the average and its assumed the above earnings are all fully taxable. For people with taxable earnings of $200,000, the pre-tax figure tends to be considerably more.

Being more generous towards the Treasurer, someone on average full-time earnings of $85,000 this year, having zero tax deductions and enjoying 3.25 per cent wages growth would reach $106,000 in 2024-25 and pay $1410 less tax that year.

But that still requires the same unlikely assumptions that make all the Treasurers big, bold future numbers possible.

Treasury appears to be brave certainly braver than the Reserve Bank in its forecast of wages growth of 3.25 per cent for 2019-20.

Beyond that year, Treasury turns positively heroic. The trick here is that the extremely brave figures are not forecasts they are merely projections based on the Goldilocks assumption that spare capacity in the economy is absorbed over five years.

The basis of the projections is spelt out each year in the budget papers, that they are based on the fairy story of everything going absolutely perfectly for the Australian economy. It never does.

If you make such a Goldilocks assumption to begin with, all the pretty numbers are forced to fall into place. Hence the budget assumes wages growth of 3.5 per cent beyond 2019-20 and GDP growth of3 per cent for as far as the eye can dream.

Thus, all the rhetoric by treasurers of both stripes about what debt and deficits might be in a decade are, and have been, nonsense a nonsense the commentariat meekly plays along with despite all the evidence of projections routinely failing.

And the rhetoric about meaningful tax cuts for average Australians and diving debt werent the only, er, spin the government seemed to be getting away with on Tuesday night. Theres also the record infrastructure investment furphy.

The Treasurer can stand and reel off the names of various highways, byways, bridges and railways most of the projects old, some new but he actually cut federal transport infrastructure investmenton Tuesdaynight.

This time last year, he took a leaf out of former treasurer Joe Hockeys PR manual to invent a big number $75 billion by adding up years until he arrived at it.

Thus, therecord $75 billion is over 10 years an average of just $7.5 billion a year. In infrastructure terms, its chickenfeed. New South Wales alone spends a multiple of that each year.

By merely extending the $7.5 billion annual average for another year, Mr Morrison effectively reduced the federal spend in real terms. Its a simple trick, but plenty fell for it.

Last years budget was framed around fixing the issues that nearly cost Malcolm Turnbull the last election. Its no surprise that this years budget would be about winning the next one. It is a very big surprise to me that its trying to do so primarily with rhetoric and spin covering a marked flattening of our progressive tax system.

As a nation, we have relied on the progressive nature of income tax to limit the growth in income inequality. It hasnt stopped the rich getting disproportionately richer, but it has kept income inequality fairly stable.

Moving to a flat marginal tax rate of 32.5 per cent for incomes from a low $41,000 a year to a high $200,000 is an ideological leap to fundamentally weaken the systems progressive nature. The winners are not middle Australia but the top decile or two.

Last years budget represented a swing by the Coalition back towards the pragmatic centre of Australian politics. This year, with nailing the inane tax cap figure of 23.9 per cent of GDP to the mast, the Liberal Party has again swung away from the centre back to the wealthier right.

This article first appeared in the New Daily