Democratic districts, for example, have grown significantly more dynamic in the last decade. Overall, “blue” territories have seen their productivity climb from $118,000 per worker in 2008 to $139,000 in 2018 as recent demographic changes and electoral sorting ensured they became better educated and more urban. Republican-district productivity, by contrast, remains stuck at about $110,000, reflecting only slight improvements of bachelor’s degree attainment and Republicans’ increasingly non-metro domain.

Relatedly, and equally striking, Democratic districts are rapidly increasing their dominance of the nation’s urban-tilting professional and digital services employment while ceding their historical, more rural shares of manufacturing and agriculture-mining activity. Just since 2008, Democratic districts’ share of professional and digital services employment surged from 63.7% to 71.1%, while their share of the nation’s manufacturing and extractive activities shrunk from 53.8% to 43.6% and 46.1% to 39.5%, respectively.

Conversely, Republican districts — failing as a group to gain traction in the new sectors — have reverted to more “traditional” ones. GOP districts’ professional and digital employment fell from 36.3% to 28.9% of the total in just 10 years, for example, while their shares of manufacturing and agriculture-mining increased from 46.2% to 56.4% and 53.9% to 60.5%, respectively.