Southern Cross audit committee chairman and board spokesman Bryan Kensington expected price increases of between 16 and 17 per cent on average.
A 16 per cent increase would add about $35 a year to the premium paid by an adult on a KiwiCare scheme.
For a family of two adults and one child with a RegularCare policy, the annual increase would be about $120.
Mr Vine said that, although capitalisation and liquidity levels remained strong, the insurer's earnings had deteriorated and no longer supported a higher rating.
The outlook for that rating was stable, with Standard & Poor's expecting operating performance to stabilise next year as the premium increases took effect.
Southern Cross is the number one health insurer in New Zealand with around 810,000 members.
- NZPA
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