Fourteen of the Country's 20 Most Expensive ZIP Codes Are in California

It's not as if any more proof were needed that California has some very rich people. Still, there's fresh evidence: It turns out that the state includes 14 of the 20 most expensive ZIP codes in the country.

But it doesn't have No.1. That distinction belongs to Sagaponack, a village in the Hamptons on eastern Long Island where the median sale price of a home is $5,125,000, according to an analysis by PropertyShark, a real estate website.

Atherton placed second, with a median sale price of $5,050,000, followed by Beverly Hills, Santa Monica and Palo Alto.

Florida was the only state other than California and New York that had a ZIP code in the top 20, as Miami Beach clinched ninth place.

In the Bay Area, Los Altos and Portola Valley were also among the most expensive ZIP codes in the United States.

The list is based only on home sales -- single-family houses, condos and co-ops -- that closed between January 2014 and May 2015. Transactions between government agencies, churches and family members were excluded, said Roxana Baiceanu, communications specialist with PropertyShark.

At the time of the 2010 U.S. Census, only 313 people lived in Sagaponack, a summer retreat for Billy Joel as well as Bill and Hillary Clinton. In 2013, the Clintons rented a mansion there that reportedly went for $200,000 a month.

The median home price in all 20 ZIP codes was more than $2 million. To put that in perspective, the median home price in the United States in May was $179,200, according to Zillow, a real estate service based in Seattle.

Business Insider recently took a look at all 20 spots in the PropertyShark survey.

It notes that the properties on Sagaponack include billionaire Ira Rennert's $248 million mansion, which has 12 chimneys, a two-lane bowling alley and 100-car garage.