Almost 30 ASX company boards have diversified since 2015, the Australian Institute of Company Directors says.

“This is an historical milestone for Australia that should be celebrated,” AICD chief executive Angus Armour said on Thursday.

The target was reached earlier this month when the last two all-male mining boards appointed highly qualified women as non-executive directors.

Thirty Per Cent Club Australia chair Nicola Wakefield Evans said women now held 500 ASX 200 board positions.

“When the push for gender diversity on the ASX 200 began, there was a view that Australia did not offer the talent pool of qualified women to achieve the targets we set,” she said.

“That myth is well and truly busted.”

A recent Towards Board Gender Parity report by the University of Queensland found Australia was one of few countries to achieve its 30 per cent target without mandated quotas or government intervention.

Armour said the shift in the approach to diversity was testament to the groups that pushed for change and the leadership and commitment of ASX chairs and directors.

But he warned it was important all chairs continued to prioritise diversity when searching for directors to ensure the success was maintained.

AICD continues to work with Thirty Per Cent Club Australia and other key stakeholders to ensure gender balance on all listed boards.

Thirty Per Cent Club Australia was launched in May 2015 with the primary objective of campaigning for 30 per cent women on ASX 200 boards.