The New Zealand Stock Exchange is a private organisation, as are the companies who list there. If a private organisation wishes to engage in acts of stupidity, that is its choice.
But the NZX is singularly important, so such acts of stupidity deserve comment.
The NZX is requiring its listed firms to disclose their gender-diversity policies - how many women they have on their boards and, worse, in their senior management.
Academic literature supports that diversity improves performance at board and senior-management level. This is true, but these studies also show that this improved performance does not improve profits.
An excellent study by LSE economists Renee Adams and Daniel Ferreira in 2008 showed women directors exercised greater oversight and diligence and had better attendance records. However, despite (or because) of this they reduced the performance of firms with good governance prior to their arrival, although they were beneficial in poorly managed firms. Generally, there was no discernable effect on the bottom line and this was in an environment with no diversity programme.