REINZ Farm Price index

Does anyone have access to this data? I can't seem to find any information on the REINZ website about how this is constructed.

Help appreciated.

Any help ?
http://www.interest.co.nz/rural/resources/farm-sales

Thanks for your quick response. I'm actually looking for historical data of the index itself:


http://www.interest.co.nz/sites/defa...-june-2014.gif