Because of the astronomical cost of living in parts of California, the federal government now classifies a family of four earning up to US$117,400 as low-income in three counties around the Bay Area.
That threshold, the highest of its kind in the nation, applies to San Francisco, San Mateo and Marin counties. It's used to determine eligibility for federal and local housing assistance programmes. (But it's different from the federal poverty guidelines.) To generate the number, officials at the Department of Housing and Urban Development factor in the median income and average housing costs in an area. The second-highest threshold is in Honolulu, according to the agency - but the third is also in the Bay Area, in Santa Clara County, the heart of Silicon Valley. The New York City area, where a family of four earning up to US$83,450 is classified as low-income, came in at No 9.
"It sounds ridiculous, but it's not," said Richard A Walker, a professor emeritus of geography at University of California, Berkeley and author of a recent book about the tech boom and displacement in the Bay Area. As the tech industry has drawn legions of highly paid workers to the area, home prices aren't the only thing that has gone up. Transportation, utilities and food are also costly.
The federal government pegs the fair market rent for a two-bedroom in the San Francisco area at US$3,121. The median home price has climbed above US$1 million, according to a recent report by the California Association of Realtors, and sales are robust.
The "low income" designation allows people to qualify for affordable housing and a variety of government programmes, such as those for first-time homebuyers.
But officials noted that a vast majority of San Francisco-area residents who get direct housing assistance, such as vouchers known as Section 8, are well below the maximum low-income standard: The average household that receives assistance makes just US$18,000. And the average wait time to make it into subsidised housing is 64 months.
In neighbouring San Mateo County, officials say the housing stock - primarily single-family homes, many on picturesque cul-de-sacs - lags far behind demand. Many residents who have been forced to move farther inland now face grueling commutes to their jobs.
"We're the epicenter of the affordability crisis we're seeing in the hotter markets throughout the US," said Ken Cole, the county's director of housing. "What it means on the ground is that teachers, first responders, people who grew up here of average income are being forced out by the high prices," he said.