How the world's richest, including Gina Rinehart, got poorer in 2015Gina Rinehart is Australia's richest person, but for how long?A quiet American is Australia's richest person 
Gina Rinehart is no longer Australia's richest person.
In the past five years Ms Rinehart has topped Forbes Australia's rich list,  but this year she has been unseated by another woman - reclusive American heiress and longtime Australian resident Blair Parry-Okeden.
Ms Parry-Okeden's net worth of $US8.8 billion ($12.5 billion) makes her the country's richest person (again) while Ms Rinehart has fallen to second place with a net worth of $US8.5 billion ($12.1 billion).
Forbes says Ms Parry-Okeden, who grew up in Hawaii and moved to her ex-husband's country of birth Australia decades ago, was recently confirmed to be an Australian citizen.
After her mother's 2007 death she inherited a quarter of US media conglomerate Cox Enterprises, America's third-biggest cable TV company
Forbes says Ms Rinehart's wealth has slipped $US3.2 billion in the past year mainly due to falling iron ore prices and a legal ruling which impacted her shareholding in Hancock Prospecting.
Ms Rinehart's wealth erosion was the largest in dollar terms, but fellow iron ore miner Andrew Forrest's wealth took the biggest percentage hit: down 41 per cent, sending him down 12 spots on the rich list to No. 22
Property baron Harry Triguboff ranks number three on this year's list, with a net worth of $US6.9 billion ($9.8 billion).
Rising rents and increased demand for his Sydney apartments helped drive up Mr Triguboff's fortune by $US1.3 billion, Forbes says.
Property sales of his apartment tower development company, Meriton, are expected to rise 70 per cent this year.
The biggest winner on the rich scale in percentage terms was Atlassian co-founder Mike Cannon-Smith. His wealth jumped 62 per cent jump to $US1.78 billion after the successful float of the software company on the US sharemarket in   December. Atlassian's co-founder, Scott Farquhar, is right behind him.
James Packer fell two spots to sixth rank with an estimated fortune of $3.5 billion.

TOP 10 RICHEST AUSTRALIANS:
1) Blair Parry-Okeden, $US8.8 billion
2) Gina Rinehart, $US8.5 billion
3) Harry Triguboff, $US6.9 billion
4) Frank Lowy, $US5 billion
5) Anthony Pratt, $US3.6 billion
6) James Packer, $US3.5 billion
7) John Gandel, $US3.2 billion
8) Lindsay Fox, $US2.8 billion
9) David Teoh, $US1.95 billion
10) David Hains, $US1.9 billion
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