Seattle’s housing market is seeing the fastest appreciation in home values in the country, according to the latest data from Zillow Group.

The real estate data powerhouse released its September Market Report report Thursday and it shows Seattle’s home price growth is even outpacing Silicon Valley’s.

Seattle’s median home value is $455,800, up 12.4 percent from a year ago. San Jose, the epicenter of the Silicon Valley tech scene, rose 10 percent over the same period. San Francisco homes are appreciating more slowly, at 6 percent. At the national level, U.S. home values rose 6.9 percent over the past year, according to Zillow.

The numbers give weight to the theory that Bay Area tech workers are increasingly moving to Seattle, in search of more affordable housing and other benefits of living in the Northwest.

Rents are growing more modestly in Seattle, with 5.5 percent year-over-year with a median monthly cost of $2,189.

September marked the ninth month in a row in which Seattle home values grew faster than any other metro region in the country. Does that mean we’re inching toward a real estate bubble?

Not exactly, says Zillow Chief Economist Svenja Gudell.

“It might be easy to assume another bubble is emerging, with home values growing 10 or 12 percent per year, but don’t worry,” she said in a statement. “The market is reacting to basic economic laws, and is behaving exactly the way we would expect it to given good overall growth.”

Seattle’s red-hot housing market is the result of a perfect storm, Gudell says. Record numbers of newcomers are moving to the city, many for high-paying tech jobs. There are 35.2 percent fewer homes for sale on the Seattle housing market than this time last year, Zillow says. The combination means demand is outpacing housing supply. Plus, mortgage rates are still relatively low, making it an attractive time to buy.