Many MPs worked into their 70s, even back in the days when attaining "three score and ten" was an aspiration many didn't achieve.

OPINION: Women shouldn't get NZ Super until two years after men.

If we set the age of eligibility for NZ Super based on evidence, we would have to discuss that as an option.

Many people advocate lifting the age of eligibility, but generally the talk is of linking it to rising life expectancies.

If it should be linked to anything, it should be health expectations.

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123RF The idea of the doddery retiree has lost a lot of currency in recent years, as people stay healthier for longer.

Your health expectation is the age to which you can expect to be reasonably healthy, and free of disability.

People below that age, are well enough to earn their living, provided ageist employers give them a chance.

Most people recognise NZ Super is only just enough to squeak by on at $37,469 before tax for a married couple, so lifting the age of eligibility for NZ Super is the only really palatable means of cutting the bill.

Rising health expectancy is a human success story.

Between 1990 and 2013 male health expectancy went up from 63.3 years to 68.2 years.

That's the better part of five bonus healthy years.

Women saw their health expectancy rise from 67.2 years to 70.5.

The question the country, and individuals face, is how do we make the economics of all this extra healthy life work?

SUPPLIED Retirement Commissioner Diane Maxwell advised Parliament in 2016 to lift the age of eligibility for NZ Super to 67 by 2034.

Perhaps, if we were being logical, we'd plump for a retirement age of somewhere around 68 or 69 based on these figures, or do a gender split at 68 for men and 70 for women.

It wouldn't change the cost of NZ Super today, but it'd slow the increase in costs.

But NZ Super policy has never been entirely logic-based. Pensions are politics.

Differing pensions ages for genders would be divisive politics, and wouldn't pass the political sniff-test.

My pick for the future of NZ Super is that the age of NZ Super will rise for both genders equally, and it will happen in a rush, possibly in the wake of an economic crisis.

But NZ Super will survive, unless we are willing to see people suffer in old age, or die on the job like back in the 1890s when New Zealand created its first age pension.

You could claim it at age 65, but the average person was dead by 60.

If, like me, you believe NZ Super will become less generous, you may want to prepare yourself.

This is both hard, and straightforward.

Straightforward, because all it involves is: Getting a money plan, making the most of KiwiSaver, getting a debt-free home, and staying employable (or developing a passive income) into your 60s.

123RF Being prepared for retirement means having money, and a home you own.

Hard because that involves planning, creating a surplus of income over expenditure, retiring debt, investing, and keeping your skills current, and yourself healthy.

As women are going to live longer, and do so more healthily, there is a special onus on them to prioritise these things.

Fortunately, most people, men and women, still choose to live as couples, which makes their money lives easier.

It also means divisive gender politics, such as different ages for men and women to draw NZ Super are extremely unlikely to eventuate.

GOLDEN RULES:

* Aim for a debt free home

* Save and invest to buy choices

* Stay fit and skilled to earn