For the fourth year in a row, Atherton has topped Bloomberg's list of wealthiest U.S. towns.

Atherton households earn an average of $525,000 annually, according to the list, published on Feb. 20.

The town became the first, and only, community to top the half-million-dollar mark since Bloomberg started compiling the index in 2017, according to the publication.

Nearby Hillsborough ranked No. 3 on the list, with an average yearly household income of $430,681. Other Peninsula towns on the list include Los Altos Hills, ranked No. 5, with an average annual household income of $405,073; and Los Altos, ranked 24th, with an average annual household income of $302,068.

Bloomberg evaluated household data for all U.S. towns with at least 2,000 households and ranked them based on average household income.

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