The average salary in Silicon Valley is well above the national average

NEW YORK (MarketWatch)—Forget the sleek startup pad. About a third of Silicon Valley young adults are still bunking with mom and dad.

In the 18- to 34 year-old segment, 32.4% lived with one or both parents from 2009 to 2013, according to a yearly report conducted by think tank Joint Venture Silicon Valley. A full 25% of the population in the area is under 18 years old, and 28% are aged 20 to 39.

While the percentage living at home is on par with the national average of 30.3%, Silicon Valley residents earn more than the average U.S. worker.

The average salary in Silicon Valley was $116,033 as of the second quarter of 2014, well above the national average of $61,489, according to the report. The majority of Silicon Valley workers, at 67.3%, were employed in high-skill, high-wage jobs and mid-skill, mid-wage jobs, the report found.

However, those numbers must be weighed against housing costs in the area. A median home cost $757,585 in 2014 and rents were $645 a month higher than average rents in California, and $1,198 a month higher than average rents in the U.S. Only 44% of first-time home buyers in Santa Clara and 34% in San Mateo counties could afford to buy a median-priced home in 2014.

Another caveat is that the segment doesn't cover the employees of startups alone--it encompasses the population of all of Santa Clara county, San Mateo county and a few cities in Santa Cruz and Alameda counties.

This is telling as Silicon Valley is home to a large income gap, with a median $91,804 difference between high-skill, high wage jobs and low-skill, low-wage jobs.

The number of young people living at home has risen since 1980, when 21.3% lived with a parent, rising to 23.4% in 1990 and 24.3% in 2000.

To get around the high rental costs, startup workers in the Silicon Valley and San Francisco area are “hacking” their housing, by living in a 50-person communal tech house or subletting a four-person room in a tech house for $1000.

Living with mom and dad may not look so bad, when compared with a house with 50 roommates.

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