SAN FRANCISCO — California's Silicon Valley will need more than a decade to replace the 185,500 net jobs lost since 2000 and employment growth will be "slow and steady," said a group representing most of the area's largest companies.

Employment should increase 1.6 percent next year, adding 21,282 jobs, said the Silicon Valley Leadership Group, whose 195 members provide almost one out of five jobs in the region. The valley's total number of jobs won't return to the 2000 level until 2016, according to a report released by the group.

"The bubble's burst," said Carl Guardino, president and chief executive of the San Jose, Calif.-based group. "Ultimately, it's healthier to have slow-and-steady growth than boom-or-bust spikes."

The valley, birthplace of Hewlett-Packard Co., Intel Corp. and Yahoo! Inc., lost more jobs in the past five years than any other top U.S. technology region. Investors pulled out of companies such as Pets.com Inc. and Webvan Group Inc., which closed after failing to make profits, leaving thousands unemployed.

Of the eight technology regions, including Boston and Seattle, studied in the survey, the valley ranked as the second least-affordable housing market after San Diego. It also had the worst roads and among the highest traffic delays, the report said.

Silicon Valley includes 40 cities in the San Francisco Bay area counties of Alameda, San Mateo, Santa Clara and Santa Cruz. Most of the job losses occurred in San Jose, Milpitas and northwest Santa Clara county, the report said.

The group's members include Apple Computer Inc., EBay Inc., Google Inc., Hewlett-Packard, Intel, KLA-Tencor Corp., Oracle Corp., and Yahoo.

"When you look at the top 10 technology regions in the world, based on productivity, access to customers and competitors, and so on, we believe Silicon Valley is still No. 1," Guardino said. "But it's no longer the only top tech region."

"For us, this is a not-so-gentle wake-up call that our competition is not resting on its hands or other body parts."

Employment in the region dropped to 1.32 million this year from 1.5 million in 2000, a decline of 12 percent, U.S. census figures show. The net loss of 185,500 is almost twice as much as the region with the second-largest loss, Boston.

A separate report released this year by a nonprofit research firm shows that Silicon Valley is adding jobs in the areas of health-care, business services, real estate and construction.

The Silicon Valley Leadership Group was created in 1978 by David Packard, the co-founder of Hewlett-Packard Co. who died in 1996, as a way for regional executives to participate in policy issues.

Its report compared Silicon Valley to Austin, Texas; Boston; Portland, Ore.; Raleigh-Durham, N.C.; San Diego; Seattle; and Washington.