NZ's Infratil to join top 10 stock index

WELLINGTON, March 11 (Reuters) - New Zealand utilities investor Infratil Ltd (IFT.NZ: Quote, Profile, Research) will be included in the index of the 10 largest listed companies , stock exchange operator NZX Ltd (NZX.NZ: Quote, Profile, Research) said on Tuesday. From April 1 Infratil will replace electricity and gas distributor Vector Ltd (VCT.NZ: Quote, Profile, Research) in the index.

In the top 15 index , plastics and resins maker Nuplex Ltd (NPX.NZ: Quote, Profile, Research) will replace national carrier Air New Zealand (AIR.NZ: Quote, Profile, Research), NZX said in a statement.

Places in the index are determined by a calculation which takes into account the size of the company and the liquidity of its shares. (NZ$1=$1.26)