We hear a lot about the many ways Americans are failing financially. Consumer credit card debt is at an all-time high. Student loan debt levels are climbing. And even though U.S. adults are doing a better job of saving than in years past, 39% still have no money available in the bank.

Now let's face it: When we think about which generation is most likely to carry debt and save inadequately, we're probably inclined to land on millennials -- you know, the so-called lazy, entitled brats who were raised to believe that the world is truly their oyster. But actually, millennials are doing a bang-up job of saving for the future, so much so that they're outperforming older generations.

20-somethings talking at a table in a restaurant

IMAGE SOURCE: GETTY IMAGES.

A good 81% of millennial workers are currently saving for retirement in some capacity, says a new report by Discover. Meanwhile, only 74% of Gen Xers and 77% of baby boomers are doing the same despite the fact that they're more likely than not to be outearning millennials.

Not only are a large chunk of millennials saving, but they're upping their game. A good 35% of younger workers saved more in 2017 than in 2016, and of those who did, that achievement boiled down to following a budget more so than any other financial move.

Of course, there are still some millennials out there who aren't actively saving for retirement, but what's more alarming is that roughly a quarter of Gen Xers and near-retirees fall into that same category. And those are the folks who really have some catching up to do.

You can't afford to wait

While it's encouraging to see millennials saving so diligently for the future, it's disheartening to read that workers in their late 30s, 40s, 50s, and beyond aren't taking the need as seriously. So if you're a Gen Xer or boomer who's coming late to the savings game, pay attention: You need to start catching up immediately. Contrary to what you may have been told, Social Security won't provide enough income for you to live off in retirement. Heck, it won't even come close.

In a best-case scenario, Social Security will replace roughly 40% of your pre-retirement income, whatever that ends up being down the line. But most seniors need a good 80% of their former earnings to stay afloat financially, and that assumes a relatively modest lifestyle. If your goal is to travel and dabble in hobbies, you'll need to do even better.

That's why it's crucial to start saving if you've yet to begin doing so -- especially since the longer you wait, the less opportunity your money will get to grow. Check out the following table, which further illustrates this concept:

If You Start Saving $300 a Month at Age:

Here's What You'll Have by Age 65 (Assumes an 8% Average Annual Return):

25

$932,000

30

$620,000

35

$408,000

40

$263,000

45

$165,000

50

$98,000

55

$52,000

TABLE AND CALCULATIONS BY AUTHOR.

Now let's be real: $300 is a reasonable amount of money to part with per month, and if you start doing just that early on, you stand to retire with upward of $900,000. (Of course, that assumes an average yearly 8% return on investments, but with stocks, that's totally doable.) But if you're, say, 40 years old and want to retire with $932,000, it'll take over $1,000 a month -- steadily -- between now and retirement to get there. And the longer you wait, the higher that monthly contribution figure will climb.

In other words, get moving on funding that IRA or 401(k). You can sock away up to $5,500 a year in the former if you're under 50 or $6,500 if you're 50 and older. Employer-sponsored 401(k)s come with even more generous annual contribution limits: $18,500 for workers under 50 and $24,500 for the 50-and-over set.

Finally, if you're among that small but substantial percentage of millennials who aren't yet saving for the future, let this be your personal wakeup call as well: The longer you wait to start funding your nest egg, the more money it'll take each month to accumulate a decent chunk of wealth. A better bet? Start young, and reap the benefits down the line. Not only will you be doing the smart thing for your future, but you'll get the bragging rights that come with putting older generations to shame.

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