Millennials tend to get a bum rap, especially when it comes to managing their finances. But new data from the National Institute on Retirement Security only drives home this point. Although 66% of millennials work for a company that sponsors a retirement plan, only 34% actually participate in those plans. All told, 66% of younger workers have no money set aside for retirement at all. And if they don't change their ways, they're going to struggle tremendously down the line.

Are you concerned about retirement?

In the aforementioned study, nearly 50% of younger workers expressed concern over not managing to retire when they want to, and 66% said they're worried about running out of money during their golden years. All of that makes sense, given the number of millennials who have yet to save.

Young adults around a table

IMAGE SOURCE: GETTY IMAGES.

If you're a younger worker who's anxious about the future, you should know that you still have a prime opportunity to amass a sizable nest egg -- provided you get moving on it right away. The longer you wait, the less you stand to accumulate, and the more you compromise your retirement as a result.

Now you're probably thinking: "There's no way I can save a bundle for retirement, given my current salary and expenses." But here's some good news: If you start saving early enough, you won't have to sock away a ton of cash each month to make a difference. Rather, you can get away with making modest yet consistent contributions that grow over time.

Check out the following table, which shows the amount of savings you might end up with after 35 years based on how much you put away on a monthly basis:

Monthly Savings Amount

Total Accumulated Over 35 Years

$100

$207,000

$200

$413,000

$300

$620,000

$400

$827,000

$500

$1.033 million

Data source: Calculations by author. Figures assume an average annual return of 8%.

Let's assume you're 32 years old and have a goal of retiring at 67. If you save a mere $100 a month, you'll wind up with over $200,000 by the time your golden years roll around. Now to be frank, that's not a whole lot over the course of what could be a 20-year retirement or longer, but it's better than nothing.

Still, watch how the numbers improve as you increase your monthly savings target. Socking away $200 a month over 35 years will leave you with over $400,000 for retirement, and if you can push yourself to $300 a month, you'll have $620,000 to work with. Better yet, if you manage to consistently set aside $500 a month during that window, you'll retire a millionaire.

Of course, you'll need to do more than just save money; you'll also need to invest it wisely. The calculations in the table above assume an 8% average annual return on investment, which is actually a bit below the stock market's average. Play it too safe with your investments, however, and you'll wind up with much less.

Finding the cash to save

Although a monthly retirement plan contribution of $100, $200, or even $300 is fairly reasonable in theory, that amount might seem undoable based on your current expenses. (And if you felt that way, you wouldn't be alone.) If so, you'll need to make an effort to eke out that cash, but you have several options.

First, take a look at your budget and see about cutting corners, whether it's moving to a less expensive apartment or dining out less frequently. Next, consider getting a side job to pocket some extra cash. (Incidentally, 14% of workers who have a side hustle took on that work to build retirement savings, so there's no reason you can't do the same.) Finally, be sure to send whatever raises or bonuses you get directly into your savings plan. This way, you're guaranteed to contribute on some level, even if you don't manage to slash your expenses or get a second gig.

No matter what steps you take to start saving for your golden years, don't put it off any longer. If there's one thing you have in your corner right now, it's time. So don't blow what could easily be a prime opportunity to set yourself up for a comfortable retirement.

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