New NZX metrics show a nearly 20% drop in total value traded last year
The two bodies will also set up two new committees for oversight and operations.
It is aimed at small to mid-sized businesses with an expected market capitalisation of $10-100m.
NZX only identified after acquisition that Westpac's Simon Power posed a conflict.
Power, who is also general manager of Westpac's private wealth management business, will formally step down from the board in May.
Volatility a result of its tightly held share register, says company.
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