What defines the American middle class? The answer can vary wildly depending on who you ask.
For some, it's a mindset and work ethic. For others, it comes down to living a certain lifestyle. And, for many, it's strictly about how much you earn.
These days, that's the most popular answer. 84 percent of Americans agree that the defining characteristic of the American middle class is income or assets, according to Northwestern Mutual's 2017 Planning & Progress Study.
Lifestyle and perspective are key elements of being middle-class as well, according to 70 percent of survey participants.