A recent study by UC Berkeley's Othering & Belonging Institute (Menendian, Gailes, and Gambhir 2021) came to an astonishing conclusion: Of large metropolitan areas in the U.S., 81% have become more segregated over the period 1990-2019. This finding contradicts the recent sociological literature on changes in segregation in the U.S., which has generally found that racial residential segregation has slowly declined since the 1970s, especially between Blacks and Whites. The major question then is: What accounts for this difference? This paper answers this question in two parts. First, it shows that the preferred segregation measure of the Berkeley study, the “Divergence Index” (Roberto 2015), is identical to the Mutual Information Index M (Theil and Finizza 1971; Mora and Ruiz-Castillo 2009; Mora and Ruiz-Castillo 2011), a measure that is mechanically affected by changes in racial diversity. Given that the U.S. has become more diverse over the period 1990 to 2019, it is not surprising that this index shows increases in segregation. Second, by making use of a decomposition procedure developed in Elbers (2021), the paper shows that once the changes in segregation are decomposed into components that account for the changing racial diversity of the U.S., the findings are in line with the sociological literature. Residential racial segregation as a whole has declined modestly in most metropolitan areas of the U.S., although segregation has increased slightly when focusing on Asian Americans and Hispanics.