Income and wealth inequality in the US has gotten steadily worse over the past decade.

As the country’s richest get even richer and the share of people below the poverty line increases, America’s middle class has been gradually disappearing. A recent analysis from the University of Chicago’s Booth School of Business found that the bottom 50% of Americans saw zero income growth over the past 35 years.

One way to understand that change is to analyze what annual salary a person currently needs to be in the top 1% of earners their age.

Business Insider used recent US census data to determine that breakdown. At 25, you’d have to be earning at least $116,000 a year to be in the top 1% of earners. By 64, that number rises to $473,000.

Here’s the full spread:

top 1 percent income by age v2

Foto: source Business Insider/Andy Kiersz, data from Minnesota Population Center IPUMS

Business Insider analyzed data from the 2015 American Community Survey, an annual survey by the US Census Bureau that aims to interview about 1% of all US households about various economic, demographic, social, and housing characteristics.

Specifically, we used individual-level data from the Integrated Public Use Microdata Series, a project of the Minnesota Population Center at the University of Minnesota, which allowed us to estimate the cutoffs for being in the top 1% of earners among full-time, year-round workers for each age in 2015.

It's worth noting that this approach has its limits - surveys like the ACS have been found to have difficulty characterizing people with extremely high incomes, and some researchers prefer to use alternate forms of data, such as tax records, when studying those at the top of the income and wealth distributions.

Being in the top 1% of incomes also doesn't necessarily mean someone is in the top 1% of total wealth, since wealth takes into account a variety of sources. Still, the large sample size of the ACS gives us a good idea of what it takes to reach the top 1% - and shows just how rich "rich" really is.