The amount of capital spending in the pipeline has fallen by $177 billion in the past three years and is set to slump even further in the coming year or two.
By the final quarter of 2015, the amount of capital investment to be worked through has fallen to $777 billion, down by $56 billion from a year earlier, according to the quarterly Investment Monitor report released by Deloitte Access Economics (DAE).
Some of that was the result of the removal of the Melbourne-Brisbane high-speed rail link from the list of likely projects - it's not seen as likely enough to go ahead in the foreseeable future.
But most of it is the decline of the resource investment boom.
The shortening of the pipeline in 2015 followed falls of $87 billion in 2013 and $33 billion in 2014.
"Australian business investment continues to slide as projects reach the end of construction and as early-stage projects are cancelled or delayed," DAE said in its report.
"Total private construction work is down markedly on last year and the falls will worsen in the next year or two."
It's not all bad news, though.
The lower exchange rate is helping the tourism and international education sectors, while low interest rates are boosting the finance sector, the report said.
At the same time, retail and housing construction are still relatively strong, despite some softening in sentiment in housing.
"The shift to lower interest and exchange rates is benefiting New South Wales, Victoria and Tasmania," DAE said.
"Meanwhile, construction on major projects is winding down fast in Queensland, while Western Australia and the Northern Territory are set to follow soon with the same magnitude."
It's the old story of the two-speed economy operating in reverse, DAE said.
Over the three years to the end of 2015, the value of investment spending in the pipeline - under way and planned - in Queensland, Western Australia and Northern Territory fell by a total of $111 billion to $460 billion.
The pipeline in the other states and territories extended by $38 billion to $240 billion.
But that will not be enough to even up the balance.