Get Sorted: Our lives span further ahead

Jumps in life expectancy make planning for our futures a moveable feast. Photo / 123RF

"I'm going to live to 100," declares my 10-year-old son matter-of-factly, as I show him some online stats about how long we're living these days.

He may be underestimating, as many of us do. His great-grandfather, after all, some years ago reached the very respectable age of 99. And with the many breakthroughs in medicine and nanotechnology that will certainly happen in my son's lifetime, any estimate of his lifespan now could be seriously off the mark.

Living longer, of course, affects our planning for the days when we'll leave our working lives behind.

How long a retirement should we be planning for? Will we outlive our money? It's hard to know exactly, but that doesn't let us off the hook for planning our futures. It's a moveable feast, but let's take a stab at it.

This week Sorted is upping its life expectancy estimates for people using its retirement planner.

The new numbers are based on statistics and are significant for 80 per cent of us: 91 years for males, 94 for females, who typically live that much longer. (These used to be 87 and 90.)

Around 20 per cent of us are likely to live beyond those limits, but the defaults can't really be set to cover everyone - otherwise they would probably have to be set around age 110!

Of course, 91 and 94 are just the suggested ages on the calculator, and we all can adjust them higher or lower to suit us. After all, how long we live will be influenced not just by genetics, but by our environment as well: our diet, our habits, our lifestyle.

The important thing is to not underestimate. That way we can make sure we don't outlive our savings.

Statistics New Zealand has its helpful "How long will I live?" spreadsheet to give you a more precise idea, based on how long we're all living now and future population projections. Plug in your year of birth, your nearest birthday, and it gives you three estimates of how long you'll live based on low, medium and high death rates in the future.

The important thing is to not underestimate. That way we can make sure we don't outlive our savings.

So much of financial planning involves making educated guesses - assumptions - on how things will pan out. We need to have a go at it and then make a plan based on what we think will happen. Perhaps we should all be planning for 30 years of retirement. (What do you think?)

That said, all we need is one biotech breakthrough, one revolutionary cure for old age, and people like my 10 year old will be winding down at the age of 130 instead of 100.

But at least he'll have more time to plan for that.

Get Sorted is written by Sorted's resident blogger, Tom Hartmann. Check out the guides and tools from Sorted – brought to you by the Commission for Financial Capability – at sorted.org.nz.