<text>  San Francisco has solidified its reputation as the city with the least affordable housing, where you need to earn more than 142,000 to afford a median-priced home. The West Coast hub of Americas booming tech industry was named the most unaffordable metropolitan area in the US by HSH.com, a mortgage tracking site, which estimated how much money a person must earn annually to afford the principal, interest, taxes and insurance payments in 27 metro areas across the country. The mortgage research company based its estimates on the National Association of Realtors fourth-quarter data for median home prices, and its own data on average interest rates for 30-year, fixed-rate mortgages and a 20 per cent downpayment. Scroll down for video . Nations housing market: Mortgage tracking site HSH.com estimated how much salary a person must bring in to afford the principal, interest, taxes and insurance payments in 27 metro areas across the country . Golden city: A home buyer is San Francisco has to earn 142,448 to keep up with monthly payments of 3,323 for a median-priced house . Going for a song: Pittsburgh ranked the most affordable metro area in the country for the third quarter in a row, requiring a salary of under 32,000 . Based on the estimates, Pittsburgh ranked the most affordable metro area in the country for the third quarter in a row, requiring a salary of under 32,000. The historic Steel City also had the lowest median home price at 135,000, and it tied Washington DC for the lowest mortgage rate at 3.98 per cent. Potential homebuyers operating on a shoestring budget also can find affordable housing in Cleveland, St Louis and Cincinnati, where required salaries range between 32,010-33,485. On a national scale, with 20 per cent down, a buyer would need to earn a salary of 48,603.82 to afford the median-priced home. Boston, New York, Los Angeles and San Diego landed on the high end of a spectrum, requiring salaries of 80,000 and higher to afford homes with median prices ranging between 383,000-493,000. The Big Apple, which has the highest mortgage rate in the nation at 4.22 per cent, was the fourth most unaffordable metro area on HSHs list, requiring homebuyers to earn 87,535 to meet the expense of a house with the median price of 393,000. San Diego, California, retained its title as the second-most-expensive metro in the country thanks to a 95,432 salary requirement. Big Apple: New York City, which has the highest mortgage rate at 4.22 per cent, was the fourth most unaffordable metro requiring homebuyers to earn 87,535 . Runner up: San Diego, California, retained its title as the second-most-expensive metro in the country thanks to a 95,432 salary requirement . San Francisco, the home of the worlds leading tech companies like Google and Apple, which has become notorious in recent years for stratospheric real estate prices, was once again crowned the king of unaffordable housing. A median home price in the Bay Area was just under 743,000 last quarter, requiring a buyer to earn 142,448 a year just to keep up with monthly mortgage payments of 3,323. The home-price gap between the San Francisco metro and Pittsburgh amounted to a whopping 607,000. Home prices in metro areas throughout the country continue to show solid price growth, up 25 per cent over the past three years on average, Lawrence Yun, NAR chief economist, told HSH.com. Low interest rates helped preserve affordability last quarter, but itll take stronger income gains and more housing supply to help meet the pent-up demand for buying. 