The number of people working past the age of 65 is rising fast.
In 2006, Statistics New Zealand says, 12% of workers were aged 65 and over - but by 2028 the same age group is predicted to make up 23% of the workforce.
Retirement Commissioner Diana Crossan says, however, that fears that baby-boomers will burden the economy may not eventuate.
As people are living for longer, Ms Crossan says, they're choosing to work for longer, which can be good for their health and costs the health system less.
The former Director of the Institute for Research on Aging, Judith Davey, says it's time to debate increasing the age of eligibility for state-funded superannuation.
Some over-65s are staying at work to support their lifestyle or to pay off debts, Ms Davey says.
The Government says it has no plans to raise the age.