The oldest millennials are 45! This tool helps plan for longevity

"Unlike one more survey or index out there about how much money you've saved, we want to look at all those big and little things that we take for granted in life," Coughlin says. "We may expect things won't change, but when a big life transition comes along – whether it's retiring from a profession, a death or unexpected sickness – many people have unintentionally ignored some of the very decisions that could help us thrive," he says.

The quiz is free online and takes about 15 minutes to complete. A score is determined by answers across eight domains, including relationships with family, friends and community, health and daily activities.

Awareness is the first step

MIT AgeLab researcher Katie Warren walks financial planner Matt Hudack through the survey at a John Hancock longevity conference, where the tool was introduced in April. John Hancock, a financial services company that provides life insurance, partnered with MIT AgeLab to develop the index and has launched an initiative to help its customers live longer, healthier lives.

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Hudack, who is in his early 60s and based in Orange County, California, clicks through questions about his neighborhood.

"Does my neighborhood have good sidewalks and places for walking?" he reads aloud. "Agree." He continues: "My neighborhood has many places for social gatherings and activities that I would enjoy? Agree."

Hudack seems healthy and fit, so it's hard to imagine a day when he couldn't drive to a pharmacy or would need help getting around. But the survey includes uncomfortable questions designed to prompt exactly that kind of thinking such as: In the event you were to need a care provider, do you know who that would be?

"Watching my 88-year-old dad and my 93-year-old father-in-law, it gives you pause for thought," Hudack says, recognizing that needs change with age. Keeping people in their homes often means modifying entrances to minimize steps, installing handrails, or relocating a bedroom and shower to the main floor. These are changes that can be anticipated in advance.

"Better to have your eyes wide open than to dig your head in the sand," Hudack says. He completed the survey and tallied his score: 89 out of 100. The average is 60.

John Hancock CEO Brooks Tingle says awareness is the first step toward change and that taking the quiz himself shifted his own thinking.

"People may make decisions about where they're going to move in, quote unquote, retirement," without thinking through some of the essential domains, he says. "For me, that might have been driven by how good the fishing was."

But taking the longevity index survey helped him realize he should be thinking more holistically as he looked decades down the road: What about the quality of health care? Would I have friends if I moved to a new town? "The general lack of preparedness struck me," he says, reflecting on that average score of 60.

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Answering questions about life transitions, community, care and home can "help reveal both the challenges and opportunities," Coughlin says.

Savings is still important

Among the harder challenges: What happens if people can no longer afford to stay in their homes, or need help with daily living but can't pay for it? Data from the Pew Research Center finds most older adults who live at home would prefer to age in place with caregiving support, if given the choice. But non-medical caregiving – like meal preparation, housekeeping and personal hygiene assistance – costs on average $80,000 a year.

"None of us know how long our savings have to last or what our life, health and ability is going to look like," says Samara Scheckler of Harvard University's Joint Center for Housing Studies. "The cost of care becomes a huge chunk of the picture when added to housing. We call that the dual burden of housing and care," she says, pointing out that these are insurmountable costs for many families.

Financial security is top of mind for most people entering the post-paycheck years.

"We did a survey where we asked people what their aspirations were for living to 100," says psychologist Laura Carstensen, director of the Stanford Center on Longevity. "The most common responses were: I hope I don't have dementia, and I hope I haven't run out of money."

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Practical concerns matter, of course, but Carstensen says the risk is that they crowd out any ability to see the upsides of a longer life. "If we only have this white-knuckled approach, we're never going to realize the potential opportunities," she says.

Planning ahead can help reframe aging

Taking steps to anticipate and adapt to the inevitable physical changes that arise as we age can open up space to imagine the possibilities.

"We really need to raise the bar and begin to daydream about what it means to be 100 and doing really well," Carstenen says.

Life expectancy in the U.S. is 30 years longer than it was in 1900 at 47 years old. And Carstensen says, when it comes to maximizing these decades, individual planning is important indeed, but we can't go it alone. Our communities shape our health outcomes as do social norms. She and her collaborators have created The New Map of Life to reexamine how societal and educational structures can support lifelong learning and thriving.

"This is about starting the conversation and then moving into preparedness and then taking action," Coughlin says. He says in the longevity space, there's an entire industry of businesses and influencers focused on extending lifespan. But what are you going to do with those years? Coughlin says the goal of the Longevity Preparedness Index is to help people think through how to design those years.

The goal is not just to live longer, but live better.