However, only 37 per cent of employers had active policies in place to attract and retain people who were aged over 55.
Mr Keegan said future generations would be working longer.
"Every generation tends to grow older than the last, so celebrating your 100th birthday is no longer science fiction.
"This ageing trend has a major impact on society, the time we spend studying, working and retiring."
Mr Keegan said it was important for businesses to recognise the values of older workers.
"There is no reason for businesses to discount mature jobseekers and instead they should be looking to them to add value to the business."
He said businesses needed stronger recruitment and retention strategies to help build a mature, flexible and skilled workforce.
"This will allow businesses to take advantage of the experience mature workers have under their belts."
However public perceptions were not so positive about older workers - 54 per cent believed it was harder for workers over 55 to acquire new skills.
But Mr Keegan countered that such judgements were unfair as productivity levels of those in the 55+ age bracket was comparable to those in other age groups.
"Kiwi businesses stand to benefit if they take advantage of the knowledge and expertise of the older generation."
Mr Keegan said many were working longer to ensure they were not financially dependent in their retirement.
He added the growing life expectancy would also change the size of the nest egg necessary to support it.
"Some estimates suggest we need to save around $350,000 for retirement."
But the study showed 35 per cent of Kiwis were only willing to save a maximum of five per cent for retirement.
"Relying on the substantially smaller pool of younger generations to prop us up through support services like superannuation will have dire economic implications," he said. "It's important New Zealanders start saving as soon as possible for retirement."
Some of the report's key findings
• More than a third of New Zealanders (36 per cent) believe children born today will live to be 100+
• More than three-quarters (79 per cent) of New Zealand workers expect to work past the retirement age
• 37 per cent of employers have active policies in place to attract and retain people
• 22 per cent of workers believe those over 55 are less productive
• 15 per cent of workers believe older workers take more sick leave than younger workers
• 54 per cent believe it is harder for those over 55 to acquire new skills.