The major tech companies make a lot of noise about their efforts to diversify their employee ranks. But how are these diversity efforts actually paying off? According to a new breakdown from Wired, it’s a very mixed bag.

“The numbers are particularly stark among technical workers—the coders, engineers, and data scientists who make these companies hum,” the magazine reported. “At Google and Microsoft, the share of U.S. technical employees who are black or Latinx rose by less than a percentage point since 2014. The share of black technical workers at Apple is unchanged at 6 percent, less than half blacks’ 13 percent share of the U.S. population.”

However, the percentage of women at Google, Facebook, Microsoft, and Apple has grown over the past five years. For example, Microsoft’s ranks were 17 percent women in 2014; by 2019, that number has crept up to 20 percent. At Facebook circa 2014, only 15 percent of the ranks were women; that number now stands at 23 percent. These are small gains, true, but more significant than changes in other areas.

To be fair, these companies have been sounding the alarm on their own diversity efforts for some time. In summer 2018, for example, Google used its annual diversity report to call out its slow progress, pointing specifically to attrition as a serious issue. “Attrition rates in 2017 were highest for Black Googlers followed by Latinx Googlers, and lowest for Asian Googlers,” the report stated. “Black Googler attrition rates, while improving in recent years, have offset some of our hiring gains, which has led to smaller increases in representation than we would have seen otherwise.”

Meanwhile, Microsoft has wrestled with reports of sexual harassment and discrimination. An email chain with dozens of horrific tales ended up in the hands of reporters from Quartz, which verified portions. Microsoft’s head of human resources promised to “do better,” but the blow-up shows that the company has some serious work to do when it comes to diversity, internal culture, and other issues (especially since it has already spent years fighting a class-action lawsuit over discrimination and harassment).    

For these companies, a diverse employee pool might translate into measurable benefits. One study by Boston Consulting Group (BCG) found that organizations with diverse leadership (i.e., thinking style, culture, gender, background) are more innovative (which is key in tech) and deliver roughly 19 percent higher revenues than those companies with monolithic workforces. Meanwhile, a Deloitte study found that 72 percent of working Americans say they would leave their organization for one with a more diversity-friendly culture—another big issue in tech, where companies sometimes struggle to keep top talent in the face of lucrative counter-offers.

So the data suggests diversity is good. But no matter how much money the biggest names in tech seem to throw at the issue, the progress remains incremental.