The blue economy contributes significantly to Brazil’s gross domestic product due to the country’s vast coastline and abundant natural resources. Oil royalties represent a major component of this wealth; yet, their association with improvements in quality of life remains unclear. The aim of this study was to analyze the performance of 193 municipalities (coastal: 101; state of Rio de Janeiro: 92) that receive more than R5 million in royalties per semester in 2022, using the socioeconomic indices IBP (Brazilian Deprivation Index), IDEB (Basic Education Index), and IQA (Water Quality Index). The results reveal conditional, non-linear, and regionally unequal relationships between oil revenues and socioeconomic indicators. Unsupervised learning identified four groups of municipalities. The group with the largest number of municipalities (n = 45) and the best performance in socioeconomic indices had a wide range of royalties (between R7 and R22 million). However, supervised analyses show that this group of municipalities, mainly from the south/southeast regions, receives relatively low oil revenues but performs well in the indices, suggesting a certain autonomy in relation to royalties. The municipalities of the state of Rio de Janeiro confirm the national trend, with cities with higher education levels benefiting, but with more specific aspects of the blue economy (water quality) not being well-represented. Policies are mandatory to redirect oil revenues to these sectors with the support of more appropriate indicators.
Bachá et al. (2026) studied this question.