NEW YORK (CNNMoney) -- How diverse are Silicon Valley's offices and executive suites? Activists have been trying for years to answer that question, but some of the industry's largest and most influential employers -- including Apple, Google, Amazon and Facebook -- closely guard that information.
Every U.S. company with more than 100 employees is required to file a one-page form each year with the Equal Employment Opportunity Commission (EEOC), an independent federal agency. Called the EEO-1, the form categorizes U.S. workers by their race and gender.
It's a blunt and imperfect measurement tool, but it's also the only hard data available for tracking the diversity of corporate America.
CNNMoney filed a Freedom of Information request in August seeking EEO-1 data from 20 companies: The tech industry's 10 biggest firms by annual sales and 10 smaller but influential firms, including Facebook and Twitter. The EEOC denied the request in full, saying it is legally prohibited from releasing that information. CNNMoney later filed the same request with the Department of Labor, and is awaiting a response.
We also asked all 20 companies to voluntarily release parts of their most recent EEO-1 report. Three companies agreed to do so: Dell, Ingram Micro (IM, Fortune 500) and Intel. (Click here for a look at the data from each company.)
Intel (INTC, Fortune 500), which posts its workforce data annually on its website, reflects the tech industry's typical demographic skew: Its roster of nearly 44,000 U.S. workers is overwhelmingly male and mostly white.
Among American adults age 25 to 64 -- typically considered the working-age population -- around 11% are African-American, but black workers account for just 3.5% of Intel's domestic workforce and 1.3% of its top officials. Hispanics are similarly under-represented: They make up nearly 15% of the American workforce, but only 8% of Intel's workforce and 3% of its management ranks.
In contrast, Asian workers -- a category that includes those of Indian descent -- have made strong inroads in the tech industry. They account for less than 5% of the U.S. working population but hold nearly 20% of the jobs at the companies CNNMoney surveyed.
Dell's (DELL, Fortune 500) data tells a similar story. More than 80% of the company's workforce is white or Asian. Dell's top management, which includes 137 executives, has no Hispanics and only one black official.
"There's nothing embarrassing about this data," says Rosalind Hudnell, Intel's chief diversity officer. "This issue is relevant for the country and for our industry. Companies can move the needle only by coming together and talking about it."
Diversity is a key talking point in corporate America. Microsoft, for example, devotes an entire section of its website to spotlighting its efforts, which include scholarships, internships and recruiting initiatives.
Are these programs working? That's impossible to measure. Microsoft refused to release its workforce demographic data. Sixteen other companies contacted repeatedly by CNNMoney also declined or ignored our request: Apple, Amazon, Cisco, eBay, Facebook, Google, Groupon, Hewlett-Packard, Hulu, IBM, LinkedIn, LivingSocial, Netflix, Twitter, Yelp and Zynga.
"Every company talks about their lovely diversity programs ... but they won't give us their data," says Aditi Mohapatra, senior sustainability analyst at Calvert Investments, which invests in socially responsible companies and conducts its own diversity research. "What gets measured, gets managed. We need something tangible and public."
Some companies shrug off those criticisms. Netflix (NFLX) is a "veritable UN," according to spokesman Steve Swasey: "We don't do anything to get diversity; we just get it. We don't focus on it, and we don't talk about it. It just is what it is. And we get the best people."
But data remain elusive. Mike Swift, a reporter with the San Jose Mercury News -- Silicon Valley's hometown newspaper -- began probing the topic in 2008 by requesting information from the federal government on the region's 15 largest local employers.
His inquiry sparked a two-year legal battle.
"I did not think it was going to take as long as it did," Swift told CNNMoney. He was surprised to be "stonewalled" by companies like Google (GOOG, Fortune 500), which calls transparency one of its core values.
Swift eventually received information on 10 of the companies he targeted, but five successfully blocked the request by convincing the Labor Department that releasing the data would infringe on their trade secrets.
Working with the data he was able to obtain, Swift found a growing problem: Hispanics and blacks made up a smaller share of the area's tech workers in 2008 than they did in 2000. And Swift said he was "shocked" at the relative scarcity of women, who in 2008 made up just 33% of the workforce at those 10 companies -- down from 37% a few years earlier.
Inspired by Swift's investigation, other groups took up the campaign. The Black Economic Council, a non-profit advocacy group, teamed with the Latino Business Chamber of Greater LA and the National Asian American Coalition to file information requests on 34 leading technology firms. Twenty-two of those requests were rejected last year.
"The companies try to make so many excuses," says Yolanda Lewis, chief deputy of the Black Economic Council. "The 'trade secrets' defense is completely ridiculous, and in any case, how long can that be valid? Give us data from several years ago, then."
Many of the companies contacted for this story cited a "pipeline problem": Not enough minorities and women are graduating with technical degrees, they say, so companies aren't able to choose from a diverse applicant pool.
As Zynga's "chief people officer," Colleen McCreary, puts it: "The workplace begins to look like the classrooms for those majors: filled with men and not as many women."
Cody Horton, a recruiting manager at Microsoft (MSFT, Fortune 500), says the tech industry needs to do a better job of showcasing the attractiveness of engineering degrees, particularly to ethnic minorities.
"There are fewer people like me in these roles, and we have a responsibility to change that," says Horton, who is black and holds a master's degree in IT management.
But waiting to target young people until their college or late high school years might be too late, says Mike Swift, the Mercury News reporter.
"Part of it needs to be primary education, as early as that sounds," Swift says. "To get these types of degrees, you need to be really good at math and science and engineering. It's a very long road."
The New Promised Land: Silicon Valley, the fourth installment in CNN's Black in America series reported by Soledad O'Brien, will premiere November 13 at 8 p.m. ET. Watch the trailer on CNN.com, and check out CNNMoney's full coverage of the project. 
