The American middle class keeps shrinking.

"The share of American adults in middle-income households also decreased, from 55% in 2000 to 51% in 2014," Pew Research Center reports. "At the same time, the share of adults in the upper-income tier increased from 17% to 20%."

Although income is just one part of class, it's a crucial element and the one that's easy to measure and track.

So just how much do you need to make to qualify as middle class these days?

Pew, which defines middle class as adults whose annual household income is two-thirds to double the national median ($55,775 as of 2016), details the national middle-income range for various household sizes.

"The income it takes to be middle-income varies by household size, with smaller households requiring less to support the same lifestyle as larger households," Pew explains.

Here's the breakdown of how much you have to earn each year to qualify as middle-income, depending on the size of your family:

Household of one: $24,042 to $72,126

Household of two: $34,000 to $102,001

Household of three: $41,641 to $124,925

Household of four: $48,083 to $144,251

Household of five: $53,759 to $161,277

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