It's an unfortunate statistic that 52% of Americans aren't happy at work, and while some of that might boil down to job-related pressure and long hours, much of it stems from feeling undercompensated. In fact, 38% of today's workers feel they're being paid less than what they should be making, according to new data from the University of Phoenix. The question is: Is it all in their heads?

Are you worth more than what you're earning?

Given that 40% of U.S. employees work more than 50 hours a week, and 20% work more than 60 hours a week, it's easy enough to feel undercompensated -- even when your salary isn't actually lower than that of your peers. After all, you're putting in so much time -- shouldn't you get paid for it?

Handing over a paycheck

IMAGE SOURCE: GETTY IMAGES.

The downside of being a salaried employee, as opposed to someone who gets paid hourly, is that you're typically not eligible for overtime. As such, you're paid the same amount each week, regardless of how much time you're putting in. But is that salary really as pathetic as you think it is?

Before you grow to resent your employer for grossly underpaying you, do some research to see what other professionals in your field are making. Glassdoor has an extremely helpful "Know Your Worth" tool that lets you compare your salary to what others with similar job titles in your geographic region are bringing in. There are other sites, like Salary.com, with similar features. It pays to gather some data before jumping to conclusions about your employer because it could be that the going rate for your job is less than what you think it is.

It's also easy to feel naturally entitled to more compensation because you work hard and put in your time. But the reality is that dedication and hustle don't always translate into more money. On the other hand, if you do some digging and come to learn that you are, indeed, being paid less than what you deserve, it's time to take action rather than resign yourself to a less-than-generous salary.

Fight for that raise

If you're certain, based on the data you've collected, that you are being undercompensated, and you want to stay at your company, you'll need to gear up to negotiate a raise. To prepare for that conversation, take the salary data you've gathered and package it up in a nice chart or graphic that proves how little you're making in comparison. Next, assemble a list of ways you've brought value to your company since getting hired. For example, if you're a web developer whose work has resulted in 20% fewer reported system bugs, highlight that statistic.

Finally, schedule a meeting with your manager at the right time so that neither of you feels pressured or rushed. Avoid early morning or late-day slots; instead, opt for a mid-morning or mid-afternoon discussion. This way, no one will be running out to catch a train, or nursing a growling stomach. The more strategic you are with that meeting, the better your chances of success.

Consider moving on

Of course, raise negotiations don't always go smoothly. If you made a strong case but are denied a raise regardless, it's time to consider finding a new company to work for. Studies have shown that workers who stay with the same employer for more than two years end up getting paid 50% less throughout their careers, so if there's nothing particularly compelling about your company, and you're not being paid what you want, it makes sense to move on.

Keep boosting your skills

If you come to find that you aren't, in fact, being undercompensated, but are still unhappy with your earnings level, you may need to bolster your skills to snag a more favorable position and salary. An estimated 39% of adults claim they're planning to enroll in a continuing-education program to further their careers. While there are benefits and drawbacks to going back to school, if you're convinced a modest amount of money and time will result in a better job with higher earnings, then it pays to take that step.

Keep in mind, however, that you don't always need to enroll in a course, or go back to school to further your career. Sometimes, shadowing the right colleagues is enough to pick up a few new skills that could be a valuable addition to your resume.

It's never a good thing to walk around thinking your salary isn't up to snuff, but if that's how you feel, do your research and then act accordingly. You deserve to be happy at work, and while money isn't everything, it's a key component of job satisfaction none of us can afford to ignore.

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