Google headquarters in Mountain View, Calif. (Marcio Jose Sanchez/AP)

A year ago, Google surprised the world by publicly releasing its diversity statistics, making a promise to update them annually. The move prompted a slew of other companies to release their own numbers as well, giving a much clearer window into the dismally small numbers of women and minorities in tech.

Now, Google is making good on its promise, despite that the new numbers show little substantial growth. On Monday, Google said the percentage of women in technology jobs at the company had risen only slightly since last year, from 17 percent to 18 percent. The percentage of women in leadership roles also barely budged, from 21 percent to 22 percent.

Meanwhile, most measures of the proportion of African Americans and Hispanics at Google — such as percentage in the total workforce, in tech jobs and in leadership roles — did not show an uptick.

"Early indications show promise, but we know that with an organization our size, year on year growth and meaningful change is going to take time," said Nancy Lee, vice president of people operations for the company, in a statement. "There isn't a simple solution to solving the diversity challenges our company and industry faces, which is why we're committed over the long run to work that spans efforts."

While the overall numbers showed little growth, Google said in its post that there are encouraging signs its efforts are paying off. For instance, it said, just 14 percent of the software engineers it hired the previous year through university outreach efforts were women, but that number grew to 22 percent this past year — outpacing the percentage of computer science graduates who are women (18 percent).

Google also said African American and Hispanic populations were making up a greater percentage of its new hires than before, though not quite enough to yet translate into an overall change in its workplace statistics.

The updated numbers show how difficult it is for companies to really move the diversity needle, even for those investing millions in such efforts. In early May, the search giant said it spent $115 million on diversity initiatives in 2014, and plans to spend $150 million in 2015.

The company has also said it is embedding engineers at historically black colleges, working with Hollywood to improve the image of what it means to be a computer scientist and expanding its recruitment pool to colleges with more minorities. It allows employees to use their "20 percent time" to focus on diversity projects, and the company's HR division is known for its data-driven approach to testing its hiring, promotion and compensation programs for fairness. 

Google has also invested significantly in training on unconscious bias, or the idea that we all have inherent, hidden biases that affect how we view and act around others. In an interview this year, the company's chief of people operations, Laszlo Bock, said the company had put a little more than half of Google's employees through the training program. He also noted that 95 percent of the company's workers have said they see it as their responsibility to take action when they see bias.

"It's sort of like a vaccination," Bock said of the company's training against unconscious bias. "You don't actually need to get to everybody, you just need to change the tone of the overall institution."

The company has had enough success with these training programs that it hopes to eventually share them with outsiders, providing a kind of "kit," Bock said, to schools or other companies. While Google was not yet ready to share details about the bias training kits, Bock said in an earlier interview that it might include some kind of online software module. He also said the company is trying to first prove the program could have the same kind of impact, in terms of reducing bias, outside Google as it has had inside the company. "Otherwise it would be kind of irresponsible and kind of arrogant," he said. 

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