Contact Energy lost about 11,500 customers in the past year.
For the year to March, Contact lost 8000 electricity customers and now has 478,500 customers.
It also lost about 3500 gas customers over the same period to 64,000.
Contact produced 739 gigawatt hours of electricity in March, 46% of which was thermal, 25% geothermal and 29% hydro.
The national average price was $112.09 per MW hour.