The NZX has dropped the embattled telephone lines company Chorus from its top 15 index.
In its place, as part of the stock exchange's regular rebalancing of its indices, Kiwi Income Property Trust joins the top 15.
Chorus's shares have fallen by more than 40 percent in the past six months.
The bladder cancer testing company Pacific Edge comes into the benchmark top 50 index in place of Hallenstein Glasson Holdings.
Pacific Edge shares have more than doubled in the past six months, while Hallenstein's have fallen by more than 35 percent.
As well, Z Energy will join the top 20 index, edging out Westpac.
Places in all the indices are determined by factors such as market value, volume of shares traded and the number of shares available to be traded.