The findings of a new United States Studies Centre report released on Thursday shed light on the depth of capital flows between the two nations.

The value of the investment relationship has risen by $350 billion to reach $1.82 trillion since the University of Sydney's USSC looked at it in 2017.

That is equivalent to about 90 per cent of the value of the entire Australian share market.

It is also 10 times larger than Australia's bilateral investment relationship with China and is $627 billion more than the UK, the second biggest partner.

More than 26 per cent of foreign investment in Australia is from the US, with more than 2000 American companies employing 272,000 workers at an economic value of $71.6 billion.

The report highlights public misconceptions about US flows of investment in Australia.

A YouGov poll for the USSC of 1054 Australians found just 17 per cent correctly identified America as the largest source of foreign investment.

More than 70 per cent believe China is number one, despite having never overtaken the US.

Accumulated US investment is now $983 billion, while China ranks ninth with investments of $78 billion.

The Trump administration's assertive trade approach is examined, noting Australia's exemption from some tariffs.

"Australia is exposed to collateral damage from the United States' pursuit of bilateral deals," the report says.

"Early evidence of the danger for Australia was China's imposition of prohibitive anti-dumping duties on its barley exports which were replaced with supplies from the United States under the bilateral trade deal."

The report's "strongest message" is for Australia to cut its company tax rate to encourage more investment from American firms.

"It is important a way is found to tackle the issue of Australia's high corporate tax rate."

Australian Associated Press