Company reporting season this year has extra interest. Yes, it will show shareholders how much they will pocket. But it will also reveal how much tax the Turnbull government is allowing the corporations to avoid.

We know companies have paid much less tax since 2013, when it was announced that “Australia is under new management”. This is clear from the Australian Tax Office annual reports, statements by ATO commissioners, the ATO transparency report, the Senate inquiry and the national accounts.

Now we can get a fair idea of how much Treasury is losing via the current tax holiday, and from which corporations. We could then, with enough time and patience, calculate by how much the gross debt — which blew out by a staggering $51.7 billion last financial year — could have been reduced.

Transurban’s operations over the year to June 2016 were fantastic! Revenue from ordinary activities — building and running toll roads — increased 18.8% over the previous year. That’s after the 2015 result was up 61.7% on 2014. Dividends rose 14% for the second year in a row. The share price soared. Directors and senior staff all got bonuses. Amazingly successful company — but it paid no company tax. In fact, it somehow gained a $69 million tax credit from the ATO.

Commercial property group Stockland had a fine year with revenue up 10% to $2.33 billion and net profit a healthy $919 million. Only 3.3% of this was paid in tax — $30 million.

[How much will a company tax cut boost ‘jobs and growth’?]

Most companies do pay some income tax. But it is clear they contribute less than during the Labor years, when 30% of net profit was collected and all figures were subject to stringent audits. Since the 2013 election, several thousand ATO personnel have gone, including audit staff.

Wesfarmers also had a pretty good 2016. Revenue from Coles, Kmart, Officeworks, Target and Bunnings were all up on last year. Revenue for the group increased from $62.4 to $66 billion. Healthy dividends and executive salaries were maintained. Yet the tax payable is down from $1004 million last year to $631 million this year.

Woolworths’ revenue was virtually the same as last year’s but also cut its tax by nearly 40%. In 2015, group sales were $60.68 billion and tax paid was $1112.8 million. In 2016, sales were $60.19 billion but tax was down to $712.6 million. A sudden drop of 36%.

Real estate developer Mirvac also had an excellent year with total revenue and other income up 42% on 2015 to more than $3 billion. Its profit before tax was above $1 billion but only $139 million was taxable. This is because most Mirvac operations are via trusts. This raises the matter of whether trust legislation now needs to be revisited. Mirvac started out in 1972 as two Sydney guys building a block of flats. It is now a huge listed corporation with market capital of $7.5 billion.

In 2012, Fortescue Metals generated $6716 million in sales revenue, gross profit of $2708 million and net profit before income tax of $2263 million. They paid $704 million in tax. This year, sales revenue was up to $7083 million and gross profit still a healthy $2019 million. But somehow the taxable profit just fell away and tax paid dropped to a puny $369 million.

[Is Treasury another victim of the great corporate tax heist?]

Boral also had much better outcomes in 2016 than last year. Revenue was up $14 million and cost of sales down $112 million. Profit before income tax (after admin and financing costs) was $284.2 million, slightly below last year’s $288.5 million. But whereas the tax paid last year was $45.1 million, it was down to just $32.2 million this year — 11.3% of net profit.

In the notes to the accounts on the tax calculations, there are the usual adjustments. Then there is a strange entry of $28.9 million in Boral’s favour referred to as “finalisation of tax matters”.

Curious, Crikey asked Boral about this and were advised: “After finalising a number of long standing tax matters during the year, we were able to write back a provision that we no longer need. This led to a benefit of A$28.9 million being recorded.” Yes, but what provision? Why? We don’t know. Does Boral? Does the ATO?

There are more annual reports to come. So it will take a while to assess precisely Treasury’s company tax shortfall now Australia is open for business. But it appears already to be a large chunk of the projected 2016-17 deficit of $37.1 billion.

So does Australia really have a spending problem? Or does it have a treasurer and finance minister problem?