If you plan to have a high-quality retirement, you'll need to take steps well in advance to prepare. Those should include investing and saving for retirement, making sure you don't have a lot of debt, and keeping your expenses reasonable -- all of which will help decrease the odds of you reaching retirement age without enough income to cover your monthly costs.

And given that people are living longer than ever now, your nest egg will have to last longer too: If you make it to 65, you're very likely to live past 80 -- perhaps by many years. 

Unfortunately, millions of Americans simply aren't doing the things necessary to make sure they're ready for a long, high-quality retirement. Keep reading to see four retirement statistics that might make your jaw hit the floor. 

Older couple with worried expressions looking at computer screen.

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1. The average retirement saver doesn't have nearly enough

By almost every piece of data available, most people nearing retirement simply don't have enough saved. According to the Employee Benefits Research Council, the average 401(k) balance for a worker in their 60s who consistently contributed was $171,641 in 2014, the most-recent data in its publication, covering some 24.9 million workers. 

Vanguard, one of America's biggest retirement plan managers, also publishes data each year about the state of the 4.1 million employee plans it manages. According to its "How America Saves 2016", the average 401(k) balance for someone 55-64 was $177,805. Vanguard also provides median balances -- the number half of savers are above and half are below -- and those are even more  unsettling. For those aged 55 to 64, the median balance was $71,579 and for 401(k) savers 65 and over, it was a $68,558.

Man keeping his piggy bank away from someone who is trying to take it.

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In other words, more than half of those 55 and older have less than $72,000 in their 401(k)s. If you follow the "4% Rule" -- which many use to guide their retirement withdrawals -- even that median amount would only generate $2,900 per year in sustainable income. For most people, that's not close to enough to bridge the gap between what Social Security will pay and their actual needs.

2. The average Social Security benefit is smaller than you think (and it's the primary income source for millions of people)

Based on the averages and medians above, you'd think more people would delay taking Social Security simply to increase their retirement income. Unfortunately, that's not the case, at least not based on the available data. According to the Social Security Administration, the average monthly retirement benefit paid in 2015 was $1,342. That works out to barely over $16,000 per year.

Photo of the outside of a Social Security office.

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Think that's mainly because of older retirees bringing the average down for new enrollees? Think again. New enrollees in 2015 averaged $1,378 per month, or $16,536 per year, only a few thousand dollars above the poverty level.  Considering that more than one-third of retirees rely almost entirely on Social Security -- particularly older retirees who have outlived their other savings -- think long and hard before you decide to retire early and take the permanant cut to your monthly benefits that doing so entails. 

3. Medicare doesn't pay for a lot of things you'll need

When you turn 65, you'll qualify for Medicare, the federal program that covers a significant amount of the healthcare needs of almost every older American. Among the things it pays for are routine medical examinations, hospitalizations for illness and injury, medical treatments, surgeries, and short-term rehabilitation. 

Nurse speaks to an older patient and fills out her chart.

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Yet there are also a lot of things Medicare won't cover. Current estimates say that on average, you'll have to pay out-of-pocket for nearly 40% of your medical expenses -- or buy supplemental insurance to cover them. According to the U.S. Department of Health and Human Services, 70% of people who live to 65 will need long-term care at some point. And nearly 80% of that care is covered neither by health insurance nor Medicare. Often, much of it is provided by family and loved ones simply because there isn't any affordable alternative. 

Just how much money are we talking about? An average couple, both over 65,can expect to spend $218,000 out of pocket over 20 years.

4. People are living longer (but not preparing for it)

We live in amazing times. Scientific and medical advances have added years to the average person's life expectancy, such that today, if you make it to 65, the odds are favor you living well past 80. Here's what data compiled by the Social Security Administration says about life expectancy:

  • A man reaching age 65 today can expect to live, on average, until age 84.3.
  • A woman turning age 65 today can expect to live, on average, until age 86.6.

And those are just averages. About one out of every four 65-year-olds today will live past age 90, and one in 10 will live past age 95.

But despite that, people haven't been taking steps to set aside more for those longer retirements. And our need for more well-stocked portfolios will be especially acute later in life, when our ability to work or otherwise generate income will be far more limited, and healthcare needs and expenses will also increase.

Older couple dressed in work clothes with sad expressions.

Image source: Getty Images.

Remember the statistic above about one-third of retirees relying almost entirely on Social Security? The vast majority are the oldest retirees who have exhausted all their other income sources, and don't have the ability to work or otherwise generate income. 

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