> In the original research, using 2014 diversity data, we found that companies in the top quartile for gender diversity on their executive teams were 15 percent

> In the original research, using 2014 diversity data, we found that companies in the top quartile for gender diversity on their executive teams were 15 percent more likely to experience above-average profitability than companies in the fourth quartile. In our expanded 2017 data set this number rose to 21 percent and continued to be statistically significant. For ethnic and cultural diversity, the 2014 finding was a 35 percent likelihood of outperformance, comparable to the 2017 finding of a 33 percent likelihood of outperformance on EBIT margin; both were also statistically significant (Exhibit 1). Correlation does not imply causality, as you know. Possibly the more successful companies face more social pressure to improve their DEI numbers, whereas no social justice advocates push on the ones who are struggling. Sampling matters. McKinsey is merely picking some data that supports their case. If you actually want to show something, do a longitudinal study: first of all, pick cohorts that match up in most other respects, then compare their relative performance within the cohort after increasing their DEI numbers. Or not doing so.