McKinsey's Diversity Matters/Delivers/Wins Results Revisited

In a series of very influential studies, McKinsey (2015; 2018; 2020; 2023) reports finding statistically significant positive relations between the industry-adjusted earnings before interest and taxes margins of global McKinsey-chosen sets of large public firms and the racial/ethnic diversity of their executives. However, when we revisit McKinsey’s tests using data for firms in the publicly observable S&P 500® as of 12/31/2019, we do not find statistically significant relations between McKinsey’s inverse normalized Herfindahl-Hirschman measures of executive racial/ethnic diversity at mid-2020 and either industry-adjusted earnings before interest and taxes margin or industry-adjusted sales growth, gross margin, return on assets, return on equity, and total shareholder return over the prior five years 2015–2019. Combined with the erroneous reverse-causality nature of McKinsey’s tests, our inability to quasi-replicate their results suggests that despite the imprimatur given to McKinsey’s studies, they should not be relied on to support the view that US publicly traded firms can expect to deliver improved financial performance if they increase the racial/ethnic diversity of their executives.