Twitter disclosed the gender and ethnicity breakdown of its employees yesterday, less than a week after US civil rights leader Reverend Jesse Jackson called on the company to release its employee diversity information.

The data is more or less in line with that released earlier by the company's Silicon Valley peers like Google, Facebook, Yahoo and LinkedIn, which showed that both women and blacks are a minority in their companies.

Silicon Valley tech companies have been under pressure to release their employee diversity data after Jackson initiated a campaign to highlight the underrepresentation of African-Americans in Silicon Valley companies, starting with a delegation in March to HP's annual meeting of shareholders.

Research shows that more diverse teams make better decisions, and companies with women in leadership roles produce better financial results, said Janet Van Huysse, Twitter's vice president for diversity and inclusion. She admitted that like its peers the company had "a lot of work to do".

Men dominate Twitter's worldwide workforce, accounting for 70% of all staff, 90% of tech staff, and 50% of non-tech staff. Male employees also make up 79% of the company's leadership.

Twitter has about 3,000 employees worldwide, of which 50% are engineers, according to its website.

Whites account for 59% of its total US employees, followed by Asians with 29%. Blacks make up for 2% of the US staff while Hispanic or Latino workers were at 3%. Twitter, like other tech companies, only provided ethnicity data for its US workers.

Jackson's Rainbow Push Coalition said that over 25,000 petitions were delivered to Twitter this past weekend demanding that they release their workforce data. "While slow to release these paltry and pathetic numbers, it's a step in the right direction," the coalition said in a statement. The Rainbow Push Coalition joined black empowerment group,, to launch a Twitter-based campaign to challenge the company.

"There is no talent deficit, there's an opportunity deficit," the coalition said. It has previously criticised tech companies for claiming that they find it difficult to recruit and retain women and minorities.

Jackson said last week that tech companies cannot explain away their hiring disparities by citing an issue with talent among blacks. Google, for example, has pointed to data that showed that blacks and Hispanics each account for under 10% of US college graduates and each earn fewer than 10% of degrees in computer science majors. The argument ignores the fact that black people are also severely underrepresented in nontechnical Silicon Valley roles, Jackson said.

Twitter has employee-led groups to promote inclusiveness and has also partnered with several organisations that address the same issue.