While Australia has never had more cash in circulation, it's disappearing from our daily lives - a trend that could be contributing to recent declines in robbery and theft.

Deputy director of the Australian Institute of Criminology, Dr Rick Brown, said that armed robbery figures have more than halved since 2001 - when property crime was at a high in the country - while unarmed robberies have dropped by around two-thirds.

Dr Brown says that we got better at preventing our possessions from being stolen, which saw shift away from stealing items and towards taking cash.

"I think from 2019 that begins to change," Dr Brown said, citing the start of the COVID-19 pandemic, when we were urged to use contactless payment methods.

"That's where we started seeing a lot less cash in particular being used, and that's the trend that's continued.

"So it's that end bit, the last four years really, that's different to what we've seen before, but is part of a bigger trend downwards of property crime being an issue."

Indeed, in the ACT, rates of property theft have overall trended down across the last decade.

Robberies have slightly declined from a height of 240 in the national capital in 2019, to 185 last year.

But while in-person property theft has declined, more Australians are being stolen from, thanks to a rise in online frauds and scams.

The Cybercrime in Australia survey, conducted in early 2023, by the AIC, found that 20 per cent of surveyed respondents in the country had been victim to an identity crime in the twelve months prior,

Meanwhile, 8 per cent of respondents said they had been a victim of fraud and scams.

Dr Brown said that online scams and fraud are allowing a smaller number of "prolific offenders" to target more Australians.

"It's a significant portion of the population that are experiencing crimes, actually far more than kind of ever experienced armed robbery or burglary for example," he said.

There is no hiding away from the fact that cash is also popular among criminals and those engaged in nefarious activities.

A spokesperson for the Australian Federal Police told The Canberra Times that "physical currency continues to facilitate the majority of criminal activity", and is the main form of currency for street-level crime.

The Australian Criminal Intelligence Commission says criminal gangs are laundering billions of dollars in cash every year.

The commission says one Sydney gang was identified laundering $1 million an hour in 2022.

So-called "money mules" are flying across the country to collect and deposit cash from illicit payments in ATMs, the commission says.

Gangs are also accumulating massive cash stashes in safe houses, recruiting students and foreign nationals to deposit large wads of notes through multiple ATMs and purchasing property in cash.

The commission has warned that money laundering is "a fundamental enabler of financial crime and is a significant and potentially lucrative criminal enterprise in itself".

In mid-2022, for example, more than $1.5 million of cash was a seized from an ACT home as part of an anti-money laundering operation that netted more than $10 million of criminal assets, including eight Canberra properties, four high-end cars, luxury goods and cryptocurrency worth about $600,000.

It is not just gangs.

Cash seized by the Australian Federal Police during a raid on two homes and a storage unit in Canberra on July 28, 2022.

People and businesses in the shadow economy use cash to evade tax, including by demanding or paying cash-in-hand for goods and services or offering discounts for cash payments.

It is a significant issue. A government taskforce in 2017 estimated that it was worth around 3 per cent of gross domestic product, around $80 billion in today's terms, and growing.

The Australian Taxation Office warns that those paid in cash without declaring it, including tips, allowances, fees and payments for goods and services are liable for prosecution.

The ATO warned sophisticated data matching techniques enabled it to identify businesses and individuals who under-report their earnings. Last financial year it successfully prosecuted 174 cases, resulting in $2.14 million of fines and almost $460,000 in reparations.

While ever the government commits to ensuring cash doesn't disappear because of its role as a vital backup to digital systems and its use for legitimate reasons, it unavoidably offers a lifeline for criminals and those in the shadow economy to continue to exploit it for their own purposes.