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#Adulting: 5 Things I Wish I Knew About Managing My Finances
Woman saving in jars ©iStockphoto.com/aldomurillo · Financial Industry Regulatory Authority

When you first enter the real world, it can be scary. For all you learned in high school or college, many of us are left feeling unprepared for the responsibilities that come with setting out on your own. This can be particularly true when it comes to managing your finances.

The fact is, very few Americans get the financial education they need in school, so many are left to figure it out on their own. In 2002, just four states required that personal finance education be offered to high school students, according to data collected by the Council on Economic Education, a non-profit group that has promoted children's financial education for more than two decades.

Since then, the numbers have improved. In 2007, the number of states requiring high school-level personal finance education increased to nine, and in 2016, it was up to 22. However, that doesn't help those who were out of high school before a personal finance education was implemented, or who were in a state that didn't have a program at all.

Learning personal finance as an adult doesn't have to be scary—in fact, it can be liberating. When you learn how to manage your money, you tend to feel more in control of your life.

If you are just getting started on your journey as an adult (or even if you are a few years in and need to level-set), here are five things I wish I knew about managing my finances when I first embarked in the real world.

Understand Compound Interest

The most important thing to understand as an adult is something called compound interest. Compound interest can either be your best friend when it is working in your favor (think retirement savings accounts) or your worst enemy if it is working against you (think credit card debt).

You either can earn interest in savings accounts or on other investments or you can owe interest on any sort of debt you carry. That interest becomes compound interest when it is added to your balance and included in future interest calculations.

An easy example of compound interest working in your favor is when you have a savings account at a bank that earns interest. Say you have $1,000 in a savings account earning 5 percent interest annually (hard to find these days, we know, although rates have begun to rise again). In month one, you would earn $4.17 in interest on the $1,000 in the account. But in month two, you would earn interest on $1,004.17, so the next month you would earn $4.18 in interest.

That may not seem like a big difference, but over time, it can really add up. If you didn't touch that account for 10 years—you didn't deposit any additional money or take any money out—and the interest rate stayed constant, you would end up with $1,647 without lifting a finger! Even if your account paid 1 percent interest annually (closer to today's national average), you would have $1,105, and with 2 percent, $1,121.