Millennials have become the generation that older age groups mock. It's a generation stereotyped as not being willing to work happy, happy to waste money on avocado toast, and used to getting at least a ribbon -- if not a trophy -- just for showing up.

Those traits generally don't make people think "fiscal responsibility", so it would be reasonable to think that Millennials aren't saving for their future. Of course, the stereotypes above aren't universal (or even necessarily common), and a new study from YCharts, The Millennial Saving & Investing Habits survey, shows that peoples ages 22-37 aren't the entitled, irresponsible people they're often portrayed as.

In fact, despite their reputation for living in the moment and not planning for a rainy day, Millennials are actually saving for retirement at pretty impressive levels. Over half (53%) of survey respondents reported saving at least 12% of their pre-tax income, while 44% save more than 15%.

A peron puts change in a piggy bank.

It's important to understand how you're saving and where it will get you. Image source: Getty Images.

It's not all good news

While Millennials defy many of the stereotypes about them, one -- the idea that they don't know quite as much as they think they do -- rings at least partially true. Of course, it's important to know that having uninformed or unrealistic views about retirement savings is not unique to any age group.

Millennials have a bit of a disconnect between what they are saving and what their goals are. Over six-in-10 (65%) of Millennials believe they will have at least a million dollars saved by age 45 or sooner.

That's not very realistic given that only 24% of those surveyed had over $100,000 in savings, while 37% have between $25,000 and $100,000. If you're 30 and have $50,000 in the bank, reaching $1 million by 45 is less than realistic.

"Based on your existing savings of $50,000 it appears that you will need to save $46,005 indexed at 8% annually in order to become a millionaire by age 45," according to Motley Fool's Be a Millionaire Calculator. "However, a million today will not be worth the same in 10 years. One million adjusted for inflation of 3% will be $1,343,916 in 10 years. You will need to save $63,422 annually (indexed at 8%) to reach that goal by age 45."

Of course, while it's trendy to talk about hitting your retirement goals by 45, the reality is that most people don't retire at 45. If you make 65 your intended retirement age the picture looks a lot better.

"Based on your existing savings of $50,000 it appears that you will need to save $2,930 indexed at 8% annually in order to become a millionaire by age 65," according to the calculator. "One million adjusted for inflation of 3% will be $2,427,262 in 30 years. You will need to save $8,968 annually (indexed at 8%) to reach that goal by age 65."

A chart shows how savings grow

Image source: The Motley Fool.

Set realistic goals

Using a savings threshold like 10% or 15% of pre-tax income is a start, but it's not the whole game. It's important to know where you stand and how much of an impact the actual amount you're saving will make on your future retirement plans.

Check in once or twice a year to make sure you're on track. If you're not, it's much better to find out early in the game -- when a correction is much easier -- than farther down the road.

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