If you're working overtime and aren't getting the pay required by law, you're part of a growing number of Americans who are now filing wage complaints against their employers under the Fair Labor Standard Act.

In 2011, the number of federal cases related to misclassification of workers, failure to pay overtime and miscalculated overtime for non-exempt workers reached an all-time high of about 7,000.

And since that many cases have already been filed this year, the problem is only getting worse.

In New York City alone, the National Employment Law Project found that 77 percent of low-wage workers who clocked more than 40 hours in a one-week period didn't get their required overtime pay, and 93 percent of workers who put in more than 10 hours in one day -- another trigger for overtime pay -- also weren't paid what they were rightfully owed.

What's to blame? Lack of clarity in overtime laws and a weak economy that's pushed companies to squeeze more work out of fewer employees, for starters. But regardless of the cause, the average low-wage employee loses out on upwards of $3,000 a year due to employer wage violations.

The good news is that the Department of Labor has taken notice. In the last fiscal year, the government agency collected over $224 million in back wages for more than 275,000 workers across the US.

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